Question 3 :
Galvanisation is a method of protecting iron from rusting, by coating with a thin layer of:<br/>
Question 4 :
During the formation of sodium chloride, sodium transfers one electron to chlorine to attain the configuration of which noble gas?
Question 8 :
An ore contains arsenic and antimony as impurities. How are they removed during the process of roasting?<br/>
Question 18 :
Which of the following metals exist in their native state in nature?<br/>(i) Ca<br/>(ii) Au<br/>(iii) Zn<br/>(iv) Ag<br/>
Question 19 :
State whether true or false :<br/><br/>All the elements having one electron in their outermost shell are metals.
Question 21 :
When manganese dioxide is heated with aluminium powder, the products obtained are _________ .<br/>
Question 22 :
The bonds present in $\left( { N }_{ 2 }{ O }_{ 5 } \right) $ are:<br/>
Question 23 :
The complete loss of an electron of one atom to another atom with the consequent formation of electrostatic charges is said to be
Question 24 :
Assertion: Ionic compounds are bad conductors of electricity.
Reason: In ionic compounds mobile ions exists.
Question 25 :
During electrolytic refining of copper.<br/>(a) Pure copper acts as anode.<br/>(b) Pure copper acts as cathode.<br/>(c) Impure copper acts as anode.<br/>(d) Impure copper acts as cathode.<br/>
Question 26 :
Process of depositing a thin layer of zinc metal on iron objects is called:
Question 27 :
During the formation of ionic bond ________transfer takes place from one atom to the others.
Question 29 :
Read the following statements and answer as true or false.<br/>Metals occur in nature only as free elements.<br/>
Question 31 :
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 32 :
In CaF$_2$, the number of electron(s) transferred from calcium to fluorine atoms are_____.
Question 34 :
The process to heat the ore in the presence of excess supply of air below its melting point is called as ________.<br/>
Question 37 :
The process of protecting iron by coating with zinc is called:
Question 38 :
The second most abundant metal present in the crust of the earth is :
Question 39 :
Which among the following metals is employed to provide cathodic protection to iron?
Question 40 :
What are the conditions for a species to act as a donor and an acceptor during dative bond formation?
Question 42 :
Which of the following is a correct property for solid magnesium carbonate?
Question 45 :
The structure of glycine (amino acid) is $H_{2}N-CH_{2}COO^{-}$ ($z$ witter ion). Select the correct statement:-
Question 48 :
Separation of impurities from the extracted metals is known as __________.
Question 50 :
Electrolysis is used in the extraction of metals from their ores.
Question 51 :
The gaseous product formed when magnesium reacts with boiling water is :
Question 55 :
Statement I: Reactivity of aluminium decreases when it is dipped in nitric acid.<br>Statement Il: A protective layer of aluminium nitrate is formed when aluminium is dipped in nitric acid.<br>
Question 56 :
The electronegativity of cesium is 0.7and that of flurione is 4.0 .Then bond formed between the two is
Question 57 :
Nickel metal is purified by the vapour phase refining process. This process is based on the fact that:<br/>
Question 58 :
Kanchan carried out an experiment in which she put one end of four rods $P,\,Q,\,R\;$and$\;S$ made up of iron, copper, carbon and zinc respectively into a container filled with boiling water. After $15$ minutes, she recorded the temperature at the undipped ends of all rods. Which rod will show the lowest temperature?
Question 59 :
An element A is soft and can be cut with a knife. This is very reactive to air and cannot be kept open in air. It reacts vigorously with water. Identify the element from the following
Question 60 :
Assertion: Magnesium is extracted by electrolytic reduction.<br/>
Reason: All metals are extracted by electrolytic reduction.
Question 63 :
A metal that exists as a liquid at room temperature is obtained by heating its sulphide in the presence of air. Identify the metal.<br/>
Question 65 :
Assertion: Sodium metal reacts with the oxygen of the air at room temperature to form sodium oxide.
Reason: Metal forms an oxide on exposure to air.
Question 67 :
Which one of the following four metals would be displaced fromthe solution of its salts by other three metals?<br>
Question 68 :
The reactivity series is a list of metals arranged in the order of their _______ activities.
Question 70 :
With reference to ionic compounds, consider the following statements:<br/>1. Ionic compounds are insoluble in alcohol.<br/>2. Ionic compounds in the solid state are good conductors of electricity.<br/>Which of these statements is/are correct?
Question 72 :
Ultrapure elements are obtained in which of the following method of metal refining?<br/>
Question 75 :
A metal $A$, which is used in thermite process, when heated with oxygen gives an oxide $B$, which is amphoteric in nature. Oxide $B$ is:<br/>
Question 76 :
Which one of the following paires of elements is most likely to form an ionic compount?
Question 78 :
Identify the compound with the strongest ionic bond among the following:
Question 80 :
$Ca+ \text{cold water} \rightarrow $<br>What will be the products formed in the above reactions?
Question 82 :
What happens when water vapour is passed over a red hot iron?
Question 83 :
The electronegativity of Caesium is $0.7$ and that of Fluorine is $4.0$. The bond formed between the two is _________________.
Question 85 :
$I$. When iron reacts with oxygen an iron oxide compound with the formula of ${Fe}_{2}{O}_{3}$ can be formed.<br/>$II$. Iron atoms form cations with a charge of $+3$ by losing $3$ electrons and oxygen atoms gain $2$ electrons to form an anion with a $-2$ charge.
Question 89 :
Identify the correct set of electrovalent compounds from the following in which the metal has electrovalency $2$ and non-metal has electrovalency $3$.<br/>(A) Calcium sulphide<br/>(B) Barium nitride<br/>(C) Magnesium phosphide<br/>(D) Aluminium nitride<br/>(E) Magnesium fluoride
Question 92 :
Which one of the following electrolytes used in Down's process of extracting sodium metal?
Question 95 :
Assertion: Ionic reactions are not instantaneous.
Reason: Oppositely charged ions exert strong forces.
Question 96 :
How much $NaCl$ can be formed by $49.5gm$ of $Na$ and $71 gm$ of $Cl$ ?
Question 97 :
Which of the following metals can displace the other three metals from their salt solutions?<br/>
Question 98 :
Write true or false for the following statements :<br>Hydrogen gas is evolved when a metal reacts with nitric acid .
Question 102 :
Among the following pairs of oxides, In which pair both are reduced by carbon?
Question 104 :
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 105 :
Which of the following family form negative ions in an ionic bond?
Question 106 :
Which of the following statement is incorrect about the extraction of lead from galena?<br>
Question 107 :
Amongst $LiCl$, $ BeCl_2,\ MgCl_2 $ and $RbCl$ the compounds with greatest and least ionic character, respectively are:
Question 108 :
Sodium is made by the electrolysis of molten mixture of about $40\% \ NaCl$ and $60\%$ $CaCl_2$ because:
Question 110 :
Which of the following equilibria would have the lowest value of $K_{p}$ at a common temperature?
Question 112 :
Which of the following sets of characteristics leads to the increase in solubility of ionic substances?
Question 114 :
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 115 :
In $Fe-$extraction, the roasting is adopted though the ore is no having any sulphide because:
Question 117 :
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 118 :
Roasting of copper pyrite ores is for which of the following purpose?
Question 120 :
When metallic copper comes in contact with moisture, a green powdery / pasty coating can be seen over it. This is chemically known as
Question 121 :
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 123 :
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 124 :
Which of the following is not a property of an ionic compound?
Question 129 :
During the formation of $NaCl$, which of the enthalpies are negative?
Question 130 :
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 132 :
Which one of the following metals will not reduce $ H_2 O? $
Question 135 :
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 136 :
In self reduction process, the species which bring about the reduction is :<br/>
Question 137 :
When a group IIA atom forms an ion, what charge does it have?
Question 138 :
ZnO in step (ii) can also be dissolved in NaOH forming :
Question 139 :
Which one of the following reactions will occur on heating $AgNO_3$?
Question 140 :
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 141 :
Select the correct reason for given statement 'Fluoride of $Al$ is ionic while chloride is covalent'.
Question 143 :
The element X reacting with chlorine forms a water soluble compound having high melting point. Element X is:
Question 144 :
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 145 :
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 147 :
Solubility of $NaCl$, $Na_2SO_4$ and $Na_3PO_4$ in water in increasing order is :
Question 149 :
Assertion: Ionic bonds are always stronger than covalent bonds.Reason: They break only when bombarded with electrons.
Question 150 :
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
