Question 7 :
The symbolic representation of one molecule of a compound is called ________.
Question 8 :
The sum of mass of all the atoms in a molecule is known as :
Question 13 :
Which of the following is used as standard for determination of atomic mass unit?
Question 16 :
_________ is the smallest unit of matter which may or may not have an independent existence, but always takes part in a chemical reaction.
Question 18 : <span>The mass number of sulfur atom is:</span><div><br/><div><span>(Given: Atomic number = 16 and number of neutrons = 16)</span></div></div>
Question 19 :
_____ are the basic units of matter and the defining structure of elements.
Question 20 :
Which one of the following properties of an element is not variable?<br>
Question 22 :
The symbolic representation of elements in a chemical compound is known as:
Question 31 :
Who was the first scientist to propose that all matter was made of small spheres called atoms?
Question 32 :
Smallest particles of matter which cannot be further divided are called:<br/>
Question 33 :
Two elements P and Q combine to form a compound. If P has $2$ and Q has $6$ electrons in their outermost shell, what will be formula of the compound formed?
Question 36 :
Molecular mass of  ${ Na }_{ 2 }{ SO }_{ 4 }$ . $10{ H }_{ 2 }O$ is:
Question 37 :
Greek philosophers,  ______and _______suggested that matter is made up of tiny indivisible particles called atoms.
Question 39 :
Weight of oxygen in $Fe_2O_3$ and FeO is in the ratio of :
Question 41 :
Which of the following is a quantity necessary to determine the molecular formula of a compound?
Question 42 : <p>The element carbon is combustible and the element oxygen also supports combustion. What can you say about the nature of compound carbon dioxide? </p>
Question 43 :
A molecule formed by atoms of the same element is called a:<br/>
Question 44 :
Which has a higher mass : 1 mole of $CO_2$ or 1 mole of $CO?$ (Mass of $C=12,$  Mass of $O=16$)
Question 45 :
The formula of a compound between any group $1$ element $M$ and any group $17$ element $X$ will be:
Question 46 :
$4.6\times 10^{22}$ atoms of an element weight $13.8$ g. What is the atomic mass of the element?<br/>
Question 47 :
How many atoms are represented by the formula $\displaystyle { K }_{ 3 }{ Fe\left( CN \right)  }_{ 6 }$ ?
Question 49 :
The number of atoms of the $He$ in $104\ amu$ is:
Question 50 : <div>One atomic mass unit is equal to?</div><div><br/></div><div>(Given, mass of one carbon-12 atom $= 1.992 \times 10^{-23}$)</div>
Question 51 :
<span>A mixture of $3\times10^{21}$ molecules of $X$ and $4.5\times10^{21}$ molecules of $Y$ weigh $1.375\ g$. If the molecular weight of $X$ is $50\ g$, then what is the molecular weight of $Y$?</span><br/>
Question 52 :
Which of the following scientist did not believe in atomic theory at all?
Question 53 :
Decreasing order of atomic weight is correct of the elements given below?
Question 54 :
An element A (atomic weight $=12$) and B (atomic weight $=35.5$) combines to form a compound X. If $4$ mol of B combines with $1$ mol of A to give $1$ mol of X. The weight of $1$ mol of X would be<span> :</span>
Question 55 :
A molecular formula is a short form representation of X. Identify X from the following.<br/>
Question 57 :
Predict the formula of a compound formed by aluminum and sulfur.
Question 58 :
The molar mass of $\displaystyle Al{ Cl }_{ 3 }$ is:
Question 60 :
The relative atomic masses of many elements are not whole numbers because
Question 61 :
An organic compound contains $4$% sulphur. Its minimum molecular weight is<span> :</span>
Question 62 : What is the approximate mass of $Ca(NO_3)_2$?<div>(Given- Atomic mass of $Ca = 40, N = 14, O = 16$)</div>
Question 63 :
The weight of one molecule of a compound of molecular formula $C_{60} H_{122}$ is:
Question 70 :
A compound contains $4$% oxygen, then the minimum molecular weight of that compound will be:
Question 71 : Choose the correct option for the following statement.<div><br/></div><div>The use of $^{12}C$ scale has superseded the older scale of atomic mass based on $^{16}O$ isotope, one important advantage of the former being: <br/></div>
Question 73 :
How many grams are there in a $7.0$ mole sample of sodium hydroxide?
Question 79 :
What is the molar mass of diacidic organic Lewis base, if $12$ g of chloroplatinate salt on ignition produced $5$ g residue?<br>
Question 80 :
What is the ratio of the number of atoms of elements potassium, chlorine, and oxygen respectively present in $245 g$ of $KCl{ { O }_{ 3 } }$?
Question 81 :
$0.3$ g of chloroplatinic acid of an organic diacidic base left $0.09$ g of platinum on ignition. The molecular weight of the organic base is<span> :</span>
Question 84 :
$25\ g$ of $M{Cl}_{4}$ contains $0.5$ mole chlorine then its molecular weight is:
Question 88 :
Which of the following contains the greatest number of atoms ?
Question 89 :
In a chemical scale, the relative mass of the isotopic mixture of oxygen atoms $ (^{16}O,^{17}O,^{18}O) $ is assumed to be equal to 
Question 90 :
The number of gold atoms in 300 mg of a gold ring of 20-carat gold ($Au = 197$: pure gold is 24 carat) is:
Question 91 :
<br/>The ratio of unpaired electrons present in d orbitals of $Co^{2+}$ and $Cr^{3+}$<span class="MathJax"><span class="MJX_Assistive_MathML">Co2+</span></span> is ____.
