Question 1 :
When chlorine reacts with sodium bromide the solution turns brown because ________.
Question 2 : <p>Oils on treating with hydrogen in the presence of palladium or nickel catalyst form fats. This is an example of :</p>
Question 4 :
$KXO_3$(s) well mixed with water, temperature of solution falls. This reaction is:<br/>
Question 5 :
Reaction of iron nails with copper sulphate solution is an example of ____________.
Question 10 :
Name the type of the following chemical reaction.$2KClO_3 \rightarrow 2KCl +3O_2$
Question 12 :
The conversion of ${Cr}_{2}{O}_{7}^{2-}$ to ${Cr}^{3+}$ during a chemical reaction is an example of:
Question 13 :
Which of the following reaction requires oxygen to be a reactant ?
Question 15 :
Aqueous solutions of magnesium chloride and silver nitrate are mixed to form solid silver chloride and aqueous magnesium nitrate.<br/><br/>The balanced molecular equation contains which one of the following terms?
Question 18 :
Which of the following is an example of the exothermic reaction ?
Question 20 :
Other signs of a chemical reaction might be an increase in temperature if heat is released or a change in _____.
Question 21 :
The reaction of hydrochloric acid with zinc oxide to form zinc chloride and water is neutralization reaction. State whether the statement is true or false
Question 25 :
$FeCl_3 + 3NaOH \rightarrow 3NaCl + Fe(OH)_3$<br/><br/>The reaction is an example of________.
Question 26 :
In $HS^, I^, R-NH_2, NH_3$ order of proton excepting tendency will be:
Question 27 :
The substance that initially involved in a chemical reaction is called a reactant.
Question 30 :
Which type of chemical decomposition reaction is the following reaction?<br>$Cu(OH)_2\xrightarrow {heat} CuO+H_2O$
Question 32 :
Three cations $A, B, C$ are allowed to react with ammonium hydroxide solution. $A$ and $B$ produce a dirty green precipitate and a reddish brown precipitate respectively, both of which do not dissolve on further addition of ${NH}_{4}OH$. $C$ gives pale blue colour precipitate with less amount of ammonium hydroxide and on further addition of ${NH}_{4}OH$, precipitate becomes soluble and deep blue colour solution is formed:
Question 33 :
In the reaction, $4Fe+3O_2\rightleftharpoons 4Fe^{3+}+6O^{2-}$ Which of the following statements is incorrect?
Question 34 :
State true or false.<br/><br/>In redox reactions, oxidation and reduction take place simultaneously.<br/>
Question 36 :
What is the difference between displacement over double displacement reactions ?
Question 37 :
State true or false.<br/>In a chemical equation, the products are written on the left-hand side and the reactants on the right-hand side with an arrow in between.
Question 38 :
AB + CD $\rightarrow$ AD + BC<br/><br/>The reaction is an example of _________.<br/><br/><br/>
Question 40 :
An oxidizing agent is always takes part in the reduction process while a reducing agent is always take part in the _______ process.
Question 42 :
Identify the type of reaction which will occur based on the information provided about the reactants:<br>${CH}_{4}(g)+{O}_{2}(g)\rightarrow$
Question 43 :
A chemical reaction in which heat is evolved is called a/an:<br/>
Question 44 :
Which of the following symbol is used to show solid precipitate?
Question 45 :
A less reactive metal replaces a more reactive metal from its salt solution in water.<br>
Question 46 :
Balanced chemical equations imply which of the following?<br>$I$. Numbers of molecules are conserved in chemical change<br>$II$. Numbers of atoms are conserved in chemical change.<br>$III$. Mass is conserved in chemical change.
Question 47 :
Calcium oxide reacts vigorously with water to produce slaked lime.<br/>$CaO(s) + H_2O(l) \to Ca(OH)_2(aq)$<br/>This reaction can be classified as:<br/>(A) Combination reaction<br/>(B) Exothermic reaction<br/>(C) Endothermic reaction<br/>(D) Oxidation reaction<br/>Which of the following is the correct option?<br/>
Question 48 :
Which of the following equations is not an example ofsingle displacementreaction ?
Question 49 :
Chlorine gas prepared from concentrated hydrochloric acid and manganese dioxide reacts with $Fe$ by_________to form__________ .
Question 50 :
Assertion: In a reaction<br/><br/>$Z n ( s ) + CuSO_4 (aq) \rightarrow ZnSO_4 (aq) + Cu(s)$<br/><br/>Zn is a reductant but itself get oxidized.
Reason: In a redox reaction, oxidant is reduced by accepting electrons and reductant is oxidized by losing electrons.
Question 53 :
Given $4NH_3(g)+5O_2(g)\rightarrow 4NO(g)+6H_2O(g)$<br>The above reaction is an example of:<br>(i)displacement reaction<br>(ii) combination reaction<br>(iii) redox reaction<br>(iv)neutralisation reaction
Question 54 :
The phenomenon of formation of simple sugar from starch in our body is the example of which reaction? 
Question 55 : <p>Ferric oxide reacts with aluminium to produce aluminium oxide and iron. The balanced chemical equation for the given reaction is :</p><p>$Fe_2O_3$ + $2Al$ $\rightarrow $ $Al_2O_3$ + $2Fe$ </p><p>Which of the following substances is oxidized in the given reaction?</p>
Question 56 :
$Zn + 2 HCl \rightarrow ZnCl_2 + H_2 \uparrow$<br/>The above reaction is an example of:<br/>
Question 57 :
When $Fe$ replaces $CuSO_4$ in the following reaction, what will be the ionic compound that forms between Fe and $CuSO_4$?
Question 58 :
In a change hydrogen peroxide gives rise' to hydrogen oxide and oxygen. This is an example of:
Question 59 :
The reduction of metal oxides can be seen in the following equations:
Question 61 :
Which of the following can act only as a reducing agent?<br>
Question 62 :
Select the correct alternative.<br/>The reaction between acid and base to form salt and water is an example of :
Question 63 :
What type of a chemical reaction is used to extract several metals from their naturally-occuring compounds like oxides or chlorides?
Question 64 :
Magnesium ribbon is burnt in an atmosphere of nitrogen gas to form solid magnesium nitride. This is a :<br/>
Question 68 :
$\displaystyle CuO+{ H }_{ 2 }\longrightarrow { H }_{ 2 }O+Cu$, reaction is an example of :<br/>
Question 69 :
Name the type of following chemical reaction.$CaCO_3 \rightarrow CaO + CO_2$
Question 70 :
$H_{2}S$ is passed through an acidified solution of copper sulphate and a black precipitate is formed. This is due to:
Question 71 :
When sodium sulphate solution reacts with barium chloride solution, the solution after the reaction contains mainly.....
Question 72 :
In the context of redox reactions, the gain of hydrogen from a substance is known as:
Question 73 : Match the item of Column I with the item of the Column II<br><table class="wysiwyg-table"><tbody><tr><td>Column I</td><td>Column II</td></tr><tr><td>a) $N{H}_{4}OH+C{H}_{3}COOH \longrightarrow C{H}_{3}COON{H}_{4}+{H}_{2}O$</td><td>(i) Thermal decomposition</td></tr><tr><td>b) $2AgBr \longrightarrow 2Ag+{Br}_{2}$</td><td>(ii) Thermit reaction</td></tr><tr><td>c) $ZnC{O}_{3} \longrightarrow ZnO+C{O}_{2}$</td><td>(iii) Photochemical reaction</td></tr><tr><td>d) $2Al+{Fe}_{2}{O}_{3} \longrightarrow 2Fe+{Al}_{2}{O}_{3}$</td><td>(iv) Neutralization reaction</td></tr></tbody></table>
Question 76 :
Magnesium reacts with acids producing hydrogen and corresponding magnesium salts. In such reactions Mg undergoes.
Question 82 :
Identify the product(s) which will be formed by using the information provided about the reactants :<br/>${C}_{4}{H}_{10}(g)+{O}_{2}(g) \rightarrow$
Question 83 :
Identify the product(s) which will be formed by using the information provided about the reactants.<br/>$NaCl(aq)+Ag{NO}_{3}(aq)\rightarrow$
Question 84 :
The activity of the metal barium is between that of sodium and potassium. It is likely that:
Question 87 :
Chlorine gas is passed in an aqueous potassium iodide solution to form potassium chloride solution and solid iodine. Identify the type of the reaction:<br/>
Question 89 :
Formation of nitric oxide from nitrogen and oxygen is a ______ reaction.
Question 90 :
In which of the following compounds, an element exhibits two different oxidation states ?
Question 92 :
Reaction of iron nails with copper sulphate solution is an example of:<br>
Question 94 :
The decomposition of mercuric oxide ($Hg)$) on heating, resulting in the formation of mercury and oxygen, is represented by the following chemical equation-<br/>$2HgO+180kJ\longrightarrow 2Hg+{O}_{2}$<br/>Which one of the following represents the heat of formation of mercuric oxide?
Question 95 :
The decomposition of $KClO_3$ to $KCI$ and $O_2$ on heating is an example of:
Question 97 :
The equation which is balanced and represents the correct product is:
Question 100 :
We know that balancing of a chemical equation is entirely based on the law of conservation of mass. However the concept of Principle of Atom Conservation (POAC) can also be related to law of conservation of a mass in a chemical reaction. So, POAC can also acts as a technique for balancing a chemical equation. For example, for a reaction $ABC_3 \rightarrow AB +C_2$ On applying POAC for A, B and C and relating the 3 equation we get : $\dfrac {n_{ABC_3}}{2}=\dfrac {n_{AB}}{2}=\dfrac {n_{C_2}}{3}$ (N= number of moles of X) Thus the coefficients of $ABC_3$, AB and $C_2$ in the balanced chemical equation will be 2,2 & 3 respectively and the balanced chemical equation can be represented as :$2ABC_3 \rightarrow 2AB +3C_2$Now answer the following question.<br/> <br/>If the weight ratio of C and $O_2$ present is 1:2 and both of the reactants completely cousumes and form CO and $CO_2$ and we will obtain a gaseous mixture of CO and $CO_2$ . What would be the weight ratio of CO and $CO_2$  in mixture?
Question 101 :
What amount of $BaSO_4$ can be obtained on mixing 0.5 mole $BaCl_2$ with 1 mole of $H_2SO_4$ ?
Question 102 :
What mass of ammonium nitrate should be heated to produce 8.96 litres of steam? [Note : Relative molecular mass of $NH_4NO_3$ is 80]
Question 103 :
If the value of $n$ is $2$, then the atomic weight of metal $M$, is
Question 104 :
A mixture of propane and benzene is burst completely in excess of oxygen at $110^{o}C$. It result the production of equal volumes of $CO_{2}(g)$ and steam (measured under identical pressure and temperature). Which of the following is correct regarding the original mixture?
Question 105 :
The reaction, when balanced, $m, n, p$ and $q$ are respectively:<br/>$K_2Cr_2O_7+ \ m FeSO_4+n H_2SO_4\rightarrow Cr_2(SO_4)_3+pFe_2(SO_4)_3+K_2SO_4+qH_2O$ 
Question 107 :
What is the minimum mass of ${ CaCO }_{ 3 }(s)$, below which it decomposes completely, required to established equilibrium in a $6.50\ litre$ container for the reaction:<br/>${ CaCO }_{ 3 }(s)\rightleftharpoons CaO(s)+{ CO }_{ 2 }(g);\space { K }_{ c }=0.005\ mole/litre$<br/>
Question 108 :
A metal ($A$) on heating in nitrogen gas gives compound $B$. $B$ on treatment with ${H}_{2}O$ gives a colourless gas which when passed through $Cu{SO}_{4}$ solution gives a dark blue-violet coloured solution. $A$ and $B$ respectively, are :
Question 110 :
Minimum amount of $Ag_2CO_3$ (s) required to produce sufficient amount of oxygen for the complete  combustion of $C_2H_2$ which produces 11.2 L of $CO_2$ at STP after combustion is_________.<br/>$Ag_2CO_3 (s) \, \rightarrow\, 2Ag (s)\, +\, CO_2 (g)\, +\, \dfrac12 O_2 (g)$<br/>$C_2H_2\, +\, \dfrac52 O_2\, \rightarrow\, 2CO_2\, +\, H_2O$<br/>
Question 111 :
Which of the following chemical reaction is balanced as well as is combustion reaction?
Question 112 :
How much $CaO$ is to be added to the furnace charge for each $1280\ kg$ of pure $CaC_{2}$ produced ?
Question 113 :
A quantity of 5.68 g of pure $ P_{4}O_{10} $ is dissolved completely in sufficient water and the solution is diluted to 250 ml. Which of the following statement (s) is/are correct?
Question 114 :
What is not a mole ratio of $ \displaystyle 6CO_2 + 6H_2O \rightarrow C_6H_{12}O_6 + 6O_2$? <br/>
Question 115 :
An amount of 0.01 mole of $ SO_{2}Cl_{2} $ is hydrolysed completely in sufficientwater (no gas is allowed to escape out ) and the solution is diluted to 200 ml. Which of the following statement is/are correct? (Ag = 108 )
Question 118 :
A quantity of $12\ g$ of magnesium is burnt completely in air $(O_{2}=20\%$ and $N_{2}=80\%$ by volume). Which of the following is/are correct statement(s) regarding this combustion?
Question 119 :
A quantity of $6\ g\ NaOH$ and $4.4\ g\ CO_{2}$ is allowed to react to form $Na_{2}CO_{3}$ or $NaHCO_{3}$ or both. Which of the following is correct statement regarding the reaction?
Question 121 :
Consider the following statements.<br/><br/>1. If all the reactants are not taken in their stoichiometric ratio, then at least one reactant will be left behind.<br/><br/>2. 2 moles of $H_2(g)$ and 3 moles of $O_2 (g)$ produce 2 moles of water.<br/><br/>3. If equal weights of carbon and oxygen are taken to produce $CO_2$, then $O_2$ is limiting reagent.<br/><br/>The above statements 1, 2, 3 respectively are (T = True, F = False):
Question 122 : For the cell $Zn(s) |Zn^{2+} (aq) || M^{x+} (aq) | M(s)$, different half cells and their standard electrode potentials are given below:<br/><table class="wysiwyg-table"><tbody><tr><td>$M^{x+} (aq/M(s))$</td><td>$Au^{3+} (aq)/Au(s)$</td><td>$Ag^+ \, /Ag(s)$</td><td>$Fe^{3+}(aq)/Fe^{2+} (aq)$</td><td>$Fe^{2+}(aq)/Fe(s)$</td></tr><tr><td>$E^o_{M^{x+}/M^{/(V)}}$<br/></td><td>$1.40$</td><td>$0.80$</td><td>$0.77$</td><td>$-0.44$</td></tr></tbody></table><br/>If $E^o_{Zn^{2+}/Zn} = -0.76 V$, which cathode will give a maximum value of $E^o_{cell}$ per electron transferred ?
Question 124 :
For the reaction of sodium with water, the balanced equation using the smallest whole numbers has which of the following coefficients?<br/>I. $1$<br/>II. $2$<br/>III. $3$<br/>Select the correct option.<br/>
Question 125 :
How many grams of ammonium nitrate will be formed in the reaction?
Question 127 :
Statement I: A basic solution has more hydrogen ions than an acidic solution.<br/>Statement II: pH is defined as the -log $[H^+]$.<br/>
Question 130 :
The hydrogen ion concentration of the oceans is about $2\times10^{-9}\space M$. What is the $pH$?
Question 131 :
Which colour appears when few drops of phenolphthalein put into test tube contains lime water?
Question 132 :
Four solutions A, B, C and D when tested with universal indicator showed pH as $4, 11, 7$ and $9$ respectively. Which one of the four solutions is neutral?<br/>
Question 134 :
Assertion: pH of a neutral solution is always $7$.
Reason: pH of a solution does not depend upon temperature.
Question 135 :
When the soil is too basic, plants do not grow well in it. To improve its quality what must be added to the soil?
Question 137 :
$pK_{a}$ of acetic acid is <b>4.741</b>. The concentration of $CH_{3}COONa$ is <b>0.01</b> M. The pH of $CH_{3}COONa$ is?
Question 138 :
The solution of bleaching powder in water is always a clear solution.<br/>
Question 140 :
$p{ K }_{ a }$ values of four acids are given below at ${ 25 }^{ o }C$. The strongest acid is:
Question 141 :
In which of the following reactions does conc.${ H }_{ 2 }S{ O }_{ 4 }$ act as an oxidising agent?
Question 142 :
If tartaric acid is not added in baking powder, the cake will taste bitter due to te presence of -
Question 144 :
Water of crystallization is the fixed number of water molecules chemically attached to a unit of a salt in its crystalline form.<br/>
Question 145 :
Aquaregia is prepared by mixing conc. $HCl$ and $conc. HNO_3$ in the ratio ________ 
Question 147 :
The chloride salt of a certain weak monoacidic organic base is hydrolysed to an extent of $3$% in its $0.1M$ solution at ${25}^{o}C$. Given that the ionic product of water is ${10}^{-14}$ at this temperature, what is the dissociation constant of the base?
Question 152 :
The acid present in the body of red ant is ________.<br/>
Question 153 :
Which part of tooth, made up of calcium phosphate, is the hardest substance in the body?
Question 155 :
$1.0 \ L$ solution is prepared by mixing $61 \ gm$ benzonic acid $(pK_a = 4.2)$ with $72 \ gm$ of sodium benzoate and then $\text{300 mL 1.0 M HBr}$ solution was added. the $pH$ of final solution is:-
Question 157 :
Which of the following methods is adopted for preparing dilute solution of ${ H }_{ 2 }S{ O }_{ 4 }$?
Question 159 :
Effervescence is seen when a bottle of soda water is opened.
Question 160 :
Calculate the pH of a solution which is 0.1 M in HA and 0.5M in NaA. Ka for HA is $1.8\times { 10 }^{ -6 }$?
Question 161 :
When $NH_{3}(0.1\ M) 50\ ml$ mix with $HCl (0.1\ M)\ 10\ ml$ then what is $pH$ of resultant solution $(Pk_{b} = 4.75)$.
Question 166 :
If $H^{+}$ion concentration of a solution is increasedby $10$ times, its $pH$ will :<br>
Question 170 :
Which one of the following is present as an active ingredient in bleaching powder for bleaching action?
Question 171 :
Sodium hydrogen carbonate when added to acetic acid evolves a gas. Which of the following statement are true about the gas?<br>(i)It turns lime water milky<br>(ii)It extinguishes a burning splinter<br>(iii)It dissolves in a solution of sodium hydroxide<br>(iv)It has a pungent odour
Question 174 :
A substances A reacts with another substances B to produce the product C and a gas D. If a mixture of the gas D and ammonia is passed through an aqueous solution of C, baking soda is formed. The substances A and B are:
Question 175 :
Bleaching powder is effective with cold water, but ineffective with hot water. This is because of:<br/>
Question 177 :
In Solvay ammonia process, sodium bicarbonate is precipitated due to :
Question 179 :
If the pH of pure water is $7$, then the hydrogen ion concentration, $[H^{+}]$ in mol L$^{-1}$ will be:
Question 180 :
When treated with $conc. HCl, MnO_{2}$ yields a gas $(X)$ which further reacts with $Ca(OH)_{2}$ to generate a white solid $(Y)$. The solid $Y$ reacts with $dil. HCl$ to produce the same gas $X$. The solid $Y$ is :
Question 181 :
$10\ mL$ of a strong acid solution of $pH=2$ are mixed with $990\ mL$ of another acid solution of $pH=4$. The $pH$ of the following solution will be:
Question 182 :
The compounds which is used in glass , soap and paper industries is :
Question 183 :
The reaction of $NaCl$ and $CaCO_3$ gives sodium carbonate. But this reaction cannot be used for the manufacture of washing soda since it is a reversible reaction.<br/>
Question 184 :
The pH of a 10 ml aqueous solution of HCI is 4. The amount of water to be added to this solution in order to change its pH from 4 to 5 is
Question 185 :
The bleaching action of the bleaching powder is due to the liberation of 
Question 186 :
1 cc of 0.1N $HCl$ is added to 999 cc solution of $NaCl$. The $pH$ of the resulting solution will be:<br/>
Question 187 :
For making cake, baking powder is taken. If at home your mother uses baking soda instead of baking powder in cake, how will it affect the taste of the cake?<br/>
Question 188 :
Assertion: Baking powder contains $NaHCO_3$, $Ca(H_ 2PO_4)_2$, starch and $NaAl(SO_4)_2$.
Reason: $\begin{matrix}NaHCO_3\\\end{matrix} $ $Ca(H_2PO_4)_{2}$ is acidic in aqueous solution. Acidic solution of $Ca(H_2PO_4)_{2}$ liberates $CO_2$ on reaction with $NaHCO_3$Starch ] as a filter$NaAl(SO_4)^2$ retarder so that $CO_2$ is given off more slowly while preparing cake or bread.
Question 190 :
State whether the given statement is true or false:<br/>Water of crystallization is the water that occurs inside crystals.
Question 191 :
The discomfort caused by indigestion due to over-eating can be cured by taking:
Question 199 :
Upon mixing equal volume of two solution of strong acids having pH values $2$ & $4$,resulting solution will have pH:
Question 200 :
Washing soda on strong heating gives sodium oxide and carbon dioxide.<br/>
Question 201 :
Equal volumes of two solutions with $p{H}=3$ and $p{H}=11$ are mixed. Then the $p{H}$ of the resulting solution is:
Question 202 :
${K}_{w}$ for ${H}_{2}O$ is $9.62\times {10}^{-14}$ at ${60}^{o}C$. What is $pH$ of water at ${60}^{o}C$.
Question 204 :
Select correct statement for <b>50ml 0.1M</b> ${ H }_{ 2 }A(aq.)$ solution ; ${ { K }_{ a } }_{ 1 }={ 10 }^{ -5 } ; { { K }_{ a } }_{ 2 }={ 10 }^{ -8 }$<br/>
Question 208 :
Read the given statements and select the correct option:<br/>Statement 1 :Backing soda does not taste sour.<br/>Statement 2 :Bases are sour in taste while acids are bitter in taste.
Question 210 :
Which of the following negative radical is present in bleaching powder?
Question 213 :
$pH$ of saturated solution of silver salt of monobasic acid $HA$ is found ton be 9. Find the $K_{sp}$ of sparingly soluble salt $Ag A$ (s).<br/>Given : $K_a(HA)=10^{10}$
Question 214 :
Which of the following salts does not contain water of crystallisation ?
Question 217 :
At $25^0$C, the solubility product of $Mg(OH)_2$ is 1.0 x $10^{-11}$. At which pH, will $Mg^{2+}$ ions start precipiating in the form of $Mg(OH)_2$ from a solution of 0.001 M $Mg^{2+}$ ions?
Question 218 :
Bleaching powder is soluble in cold water giving a milky solution due to:
Question 219 :
Which one of the following solutions will have the highest pH value?
Question 220 :
The more commonly used baking powder contains about 30% $NaHCO_3$, 20% $NaAl(SO_4)_2$, 10% $Ca(H_2PO_4)_2$ and 40% starch. Which of the following statements are correct?<br/>
Question 221 :
The $pH$ of a ${ 10 }^{ -9 }\ M$ solution of $HCl$ in water is :<br>
Question 223 :
$NaHCO_{3}$ can be used on its own to make cakes or bread. Baking powder is more commonly used, and contains $NaHCO_{3}$, $Ca(H_{2}PO_{4})_{2}$ and starch. An improved combination baking powder contains about 40% starch, 30% $NaHCO_{3}$ 20% $NaAl(SO_{4})_{2}$ and 10% $Ca(H_{2}PO_{4})_{2}$Answer the following questions based on above study.<br/><br/>In improved baking powder, $NaAl(SO_{4})_{2}$ is used for :
Question 224 :
The indicator constant for an acidic indicator , HIn is $ 5 \times 10^{-6}  M $. this indicator appears only in the colour of acidic from when $ \frac { [In^- ] }{ [HIn]} \le \frac {1}{20} $ and it appears only in the colour of basic form when $ \frac { [HIn]}{[In^-]} \le \frac {1}{40} . $ the pH range of indicator is:
Question 225 :
Iso-electric point of alanine is (pH = $6$). At which pH, maximum concentration of zwitter ion of alanine will be present?
Question 226 :
The $pH$ at which a 0.01 M ${ Al }^{ +3 }$ solution is 99.99% precipitated is: $\left( { K }_{ sp } \ \ Al\left( OH \right) _{ 3 }=1\times { 10 }^{ -18 }at\quad 25 \right) $
Question 228 :
The first and second dissociation constants of an acid $H_{2}A$ are $1.0\times 10^{-5}$ and $5.0\times 10^{-10}$ respectively. The overall dissociation constant of the acid will be:
Question 229 :
The ions responsible for the bleaching action of bleaching powder and the ions responsible for loss of bleaching action of bleaching powder due to the storage for long time respectively are:<br/>
Question 231 :
What is the correct increasing order of the $pH$ values of the following solutions with equal concentrations?
Question 233 :
The $pH$of $0.1 M$ solution of the following salts increases in the order
Question 234 :
When ethyl alcohol is heated with a paste of bleaching powder, we get a compound in which the function of bleaching powder is: 
Question 235 :
To $1.0 L$ solution containing $0.1$ mol each of $NH_3$ and $NH_4Cl, 0.05$ mol NaOH is added. The change in pH will be : $(pK_a$ for $CH_3 COOH=4.74$)
Question 236 :
Percentage ionisation of water at certain temperature is $3.6\times { 10 }^{ -7 }$%. Calculate ${K}_{w}$ and $pH$ of water.
Question 237 :
The $pH$ of a buffer solution containing equal molar concentration of a week base and its chloride ($K_{b}$ for weak base $=2\times 10^{-5}$) is :
Question 238 :
When chlorine is passed over dry slaked lime at room temperature, the main reaction product is:
Question 240 :
$1\ cc$ of $0.1N$ $HCl$ is added to $1$ litre solution of sodium chloride. The $pH$ of the resulting solution will be:
Question 242 :
$1.0$ ml of a solution of $HCl$ with a $pH$ of $4.0$ is added it to $9.0$ ml of distilled water, the $pH$ of the final solution will be:
Question 243 :
Dissociation constants of $CH_3COOH$ and $NH_4OH$ in aqueous solution are $10^{-5}$. If pH of a $CH_3COOH$ solution is $3$. What will be the pH of $NH_4OH$?
Question 244 :
$\dfrac{N}{10}$ acetic acid was titrated with $\dfrac{N}{10}$ $NaOH$. when 25%, 50% and 75% of titration is over then the $pH$ of the solution will be (respectively): $[K_a = 10^5]$ 
Question 245 :
The third dissociation constant of $H_{3}PO_{4}$ is $1.3\ \times 10^{-12}$. Assume that the hydrolysis proceeds only in the first step, the $pH$ of $0.1\ M\ K_{3}PO_{4}$ solution is:
Question 246 :
One mole of ammonia was completely absorbed in one litre solution each of<br/>I. $1\ M\ HCl$<br/>II. $1 \ M\ CH_3COOH$ <br/>III. $1\ M\ H_2SO_4$ at $298$ K<br/>The decreasing order for the $pH$ of the resulting solution is:(Given: $K_b (NH_3) = 4.74$)
Question 247 :
The $pH$ of $HCl$ is 1. $1.10\ ml$ of this solution is reacted with $40\ ml$ of $NaOH$ solution whose $pH=12$. The $pH$ of resulting solution is: $(\log(1.2)=0.108)$<br/>
Question 249 :
$NaHCO_{3}$ can be used on its own to make cakes or bread. Baking powder is more commonly used, and contains $NaHCO_{3}$, $Ca(H_{2}PO_{4})_{2}$ and starch. An improved combination baking powder contains about 40% starch, 30% $NaHCO_{3}$ 20% $NaAl(SO_{4})_{2}$ and 10% $Ca(H_{2}PO_{4})_{2}.$ Answer the following questions based on above study.<br/>Rise in bread and cakes is due to______ when it decomposes between $50^{o}C$ and $100^{o}C$. 
Question 250 :
The $pH$ of $0.1M$ solution of the following salts increases in the order:
Question 252 :
$NaHCO_{3}$ can be used on its own to make cakes or bread. Baking powder is more commonly used, and contains $NaHCO_{3}$, $Ca(H_{2}PO_{4})_{2}$ and starch. An improved combination baking powder contains about 40% starch, 30% $NaHCO_{3}$ 20% $NaAl(SO_{4})_{2}$ and 10% $Ca(H_{2}PO_{4})_{2}.$ Answer the following questions based on above study.<br/>$Ca(H_{2}PO_{4})_{2}$ in baking powder:
Question 254 :
Number of $OH^-$ in 1 mL solution of pH = 13 is:
Question 255 :
Baking powder used to make a cake is a mixture of starch, $NaHCO_3$ and $Ca(H_2PO_4)_2$. The function of $Ca(H_2PO_4)_2$ is:<br/>
Question 257 :
The aqueous solution of which one of the following is basic?
Question 258 :
Which is the correct for the following reaction: <br/>$B\, (OH)_3\, +\, H_2O\, \rightarrow \, [B(OH)_4]^-\, +\, H^+$
Question 259 :
Substance $X$:<br/>(I) reacts with $H_2S$ to produce white turbidity.<br/>(II) changes light green solution of $FeSO_4$ into yellow colour.<br/>(III) reacts with moisture to give pungent smelling gas.<br/>Hence $X$ is:
Question 261 :
Galvanisation is a method of protecting iron from rusting, by coating with a thin layer of:<br/>
Question 264 :
Coulomb's law is used to calculate the energy of an ion pair.
Question 265 :
A magnesium ion has a net positive charge while the magnesium atom has __________. 
Question 269 :
In case of formation of ionic compounds, the electronegativity difference between them is less than 1.7.<br/>
Question 272 :
State whether true or false :<br/><br/>All the elements having one electron in their outermost shell are metals.
Question 273 :
Electrolysis is used in the extraction of metals from their ores.
Question 275 :
When an element of very low ionization potential reacts with an element of very high electron affinity, then :
Question 281 :
The attraction between molecules and salt, when a salt is dissolved in water molecules, is :
Question 282 : Which one of the methods given in column- I is applied for the extraction of the metal given in column II:<br/><blockquote><table class="wysiwyg-table"> <tbody><tr> <td><b>Column -I</b></td> <td><b>Column - II</b></td> </tr> <tr> <td>(A) Electrolytic reduction</td> <td>(i) Aluminium</td> </tr> <tr> <td>(B) Reduction with carbon</td> <td>(ii) Zinc</td> </tr> <tr> <td>(C) Reduction with aluminium</td> <td>(iii) Sodium</td> </tr> <tr> <td> </td> <td>(iv) Iron</td> </tr> <tr> <td> </td> <td>(v) Manganese</td> </tr> <tr> <td> </td> <td>(vi) Chromium</td> </tr></tbody></table></blockquote>
Question 285 :
$Li$, $K$, $Ca$, $Na$, $Mg$, $Al$, $Zn$, $Fe$, $Pb$, $Cu$, $Hg$, $Ag$<br/>Which metal will displace hydrogen from acids but not water?
Question 287 :
Which of the following is a correct property for solid magnesium carbonate?
Question 288 :
During extraction of metals, electrolytic refining is used to obtain pure metals. Material which will be used as anode, for refining of silver metal by this process, is:<br/>
Question 290 :
We have $CuSO_4$ solutions (blue) in two beakers A and B. In beaker A we add Ag pieces and in B we add Zn pieces. What will happen in A if :<br/>1. $Cu^{2+}$ is reduced to Cu<br/>2. no reaction.
Question 291 :
Assertion: Zinc is used in the galvanization of iron.
Reason: Its coating on iron articles increases their life by protecting them from rusting.
Question 294 :
The structure of glycine (amino acid) is $H_{2}N-CH_{2}COO^{-}$ ($z$ witter ion). Select the correct statement:-
Question 300 :
The process of protecting iron by coating with zinc is called:
Question 301 :
In electrolytic refining, which one is the anode and which is cathode?
Question 302 :
Process of depositing a thin layer of zinc metal on iron objects is called:
Question 303 :
Separation of impurities from the extracted metals is known as __________.
Question 304 :
When manganese dioxide is heated with aluminium powder, the products obtained are _________ .<br/>
Question 307 :
The bonds present in $\left( { N }_{ 2 }{ O }_{ 5 } \right) $ are:<br/>
Question 311 :
The sodium is made by electrolysis of a molten mixture of 40% NaCl and 60% $CaCl_2$ because :
Question 314 :
Assertion: In the formation of water molecule, both hydrogen and oxygen atoms attain octet of electrons.
Reason: Oxygen atom forms two ionic or electrovalent bonds with two hydrogen atoms.
Question 315 :
An element reacts with oxygen to give a compound with a high melting point. This compound is also soluble in water. The element is likely to be:
Question 316 :
During the formation of $NaCl$, element $X$ is oxidised and element $Y$ is reduced. Then elements $X$ and $Y$ are respectively :
Question 317 :
Formation of anion from a neutral atom $X$ is favoured by :
Question 318 :
If $A, B, C, D, E, F, G, H, I, J, K$ represents metals in the decreasing order of their reactivity, which one of item is most likely, to occur in a free state in nature?
Question 322 :
The electrolysis reduction technique is used in the extraction of :
Question 323 :
Assertion: Roasting is a process in which the ore is heated strongly in absence of air.
Reason: Concentration of sulphide ore is done by calcination.
Question 327 :
Of the following, the metals that cannot be obtained by electrolysis of the aqueous solution of their salts are ________________.
Question 328 :
When sodium reacts with cold water, then the product formed will be:
Question 329 :
Name the following: A metal which does not react with cold water but reacts with steam.
Question 331 :
A metal which is unaffected by dilute or concentrated acids is :<br/>
Question 333 :
Reaction of hydrochloric acid with zinc oxide to form zinc chloride and water is a neutralization reaction.
Question 334 :
The products of the following reaction are $Si{ O }_{ 2 }+C\xrightarrow [ ]{ \Delta } $
Question 335 :
Which one of the following metals do not react with cold as well ashot water?<br>
Question 336 :
Which of the following does not conduct electricity in its molten state?
Question 337 :
Impure metal forms a volatile compound (X) with CO then on heating  (X) gives pure metal. <br/>The Metal is :
Question 338 :
Which of the following metalsoccur in free as well as combined state?
Question 339 :
Sodium metal is prepared commercially by electrolysis of fused $NaCl$ by:
Question 342 :
In electrolytic refining, ______ is used as anode and _______ is used as cathode.
Question 344 :
Assertion: To protect iron from rusting it is coated with a thin layer of zinc.
Reason: The zinc forms a barrier against corrosion in that the steel underneath does not come into contact with water / moisture in the air
Question 347 :
When dilute hydrochloric acid is added to granulated zinc placed in a test tube, the observation made is _____________.
Question 348 :
A chloride dissolves appreciably in cold water. When placed ona platinum wire in Bunsen flame, no distinctive colour is noticed. The cation of chloride is :
Question 349 :
Zinc sulphate forms a colourless solution in water. Colour on adding copper  is :<br/>
Question 353 :
Assertion: An ionic solid is a good conductor of electricity.
Reason: An ionic solid is composed of positive and negative ions joined together by electrostatic forces.
Question 354 :
Roasting of sulphides gives the gas $X$ as a byproduct. This is colourless gas with choking smell of burnt sulphur and causes great damage to respiratory organs as a result of acid rain. Its aqueous solution is acidic, acts as a reducing agent and its acid has never been isolated. The gas $X$ is:<br/>
Question 355 :
Borax is used as cleansing agent because on dissolving in water it gives ________________.
Question 359 :
Among $Mg,Cu,Fe,Zn$ the metal that does not produce hydrogen gas in reaction with hydrochloric acid is
Question 360 :
Which of the following process is used in the extractive metallurgy of magnesium ?
Question 361 :
Which one of the following reactions will occur on heating $AgNO_3$?
Question 365 :
Which of the following is not a property of an ionic compound?
Question 367 :
Consider the following statements. Roasting is carried out to:<br/>(i) convert sulphide to oxide and sulphate.<br/>(ii) to remove impurities of $CuS$ and $FeS$ present in the ore of tin stone $(SnO_2)$ as $CuSO_4$ and $FeSO_4$.<br/>(iii) melt the ore.<br/>(iv) remove arsenic and sulphur impurities.<br/>Of these statements:<br/>
Question 372 :
Mark the correct statements:<br/><br/>(i) mercury can be refined by the process of distillation.<br/><br/>(ii) In poling, the molten impure metal is stirred with green poles of wood.<br/><br/>(iii) In electrolyte refining of metals, impure metal is made as cathode and a thin strip of pure metal is made as anode.
Question 374 :
Which set of compounds in the following pair of ionic compounds has the higher lattice energy?<br/>(I) $KCl$ or $MgO$<br/>(II) $LiF$ or $LiBr$<br/>(III) $MgF_2$ or $NaCl$<br/>
Question 375 :
Assertion: Ionic bonds are directional in nature whereas covalent bonds are non-directional.
Reason: According to orbital overlap concept, the formation of a covalent bond between two atoms results by pairing of electrons present in the valence shell having same spins.
Question 376 :
Assertion: Ionic bonds are always stronger than covalent bonds.Reason: They break only when bombarded with electrons.
Question 377 :
When a group IIA atom forms an ion, what charge does it have?
Question 378 :
Roasting of copper pyrite ores is for which of the following purpose?
Question 382 :
Select the correct reason for given statement 'Fluoride of $Al$ is ionic while chloride is covalent'.
Question 383 :
For purification of alumina, the modern processes most useful when (i) The impurity present is lot of iron oxides and (ii) the impurity present is a lot of silica, are
Question 384 :
ZnO in step (ii) can also be dissolved in NaOH forming :
Question 385 :
Assertion: In smelting, roasted ore is heated with powdered coke in presence of a flux.
Reason: Oxides are reduced to metals by $C$ or $CO$. Impurities are removed as slag.
Question 386 :
Which of the following has a bond formed from the transfer of electrons?
Question 388 :
In Down's process for the extraction of sodium, the melting point of $NaCl$ is lowered from $803^{0}C$ to $600^{0}C$.<br/><br/>Choose the correct statement(s) regarding this.<br/>a) It is done in order to avoid vapourisation of metallic sodium.<br/>b) It is done in order to avoid corrosive action of sodium and chlorine on the vessel at the high temperature.<br/>c) It is done by mixing sufficient amounts of $CaCl_2$.<br/>
Question 389 :
Which of the following family form negative ions in an ionic bond?
Question 390 :
In self reduction process, the species which bring about the reduction is :<br/>
Question 391 :
Roasting is carried out to :1) convert sulphide to oxide and sulphate. <br/>2) remove the water of hydration. <br/>3) melt the ore. <br/>4) remove arsenic and sulphur impurities.<br/>Choose the correct options.
Question 392 :
Statement 1: Powdered zinc reacts faster with acid than a larger piece of zinc.<br/>Statement 2: Powdered zinc has a greater surface area.
Question 393 :
Which of the following equilibria would have the lowest value of $K_{p}$ at a common temperature?
Question 395 :
In $Fe-$extraction, the roasting is adopted though the ore is no having any sulphide because:
Question 397 :
Among the following pairs of oxides, In which pair both are reduced by carbon?
Question 399 :
Which of the following sets of characteristics leads to the increase in solubility of ionic substances?
Question 400 :
Sodium is made by the electrolysis of molten mixture of about $40\% \ NaCl$ and $60\%$ $CaCl_2$ because:
Question 401 :
$FeS + HCl \rightarrow A + B(g)$<br/><br/>Gas $B$ is passed into aqueous solution of $C$ to form $A$. Select correct statements based on the above facts.
Question 402 :
Assertion (A): In the electrolysis of aqueous NaCl,Na is preferentially discharged at the mercurycathode forming sodium amalgam.<br>Reason (R) : It is due to the fact that hydrogenhas a high over voltage at mercury cathode.<br>
Question 403 :
The element X reacting with chlorine forms a water soluble compound having high melting point. Element X is:
Question 404 :
Which of the following statement is incorrect about the extraction of lead from galena?<br>
Question 405 :
Amongst $LiCl$, $ BeCl_2,\ MgCl_2 $ and $RbCl$ the compounds with greatest and least ionic character, respectively are:
Question 408 :
Assertion: Statement $\displaystyle -$ 1 : The first ionisation energy of N is greater than O.
Reason: Statement $\displaystyle -$ 2 : N atom has half filled p $\displaystyle -$ orbitals.
Question 409 :
During the formation of $NaCl$, which of the enthalpies are negative?
