Mass, Volume and Mole Relationship

Q.

Which has more number of atoms, $100$ grams of sodium or $100$grams of iron (given, atomic mass of $\mathrm{Na}=23\mathrm{u}$, $\mathrm{Fe}=56\mathrm{u}$$100\mathrm{g}$)?

Q.

Nitrogen reacts with oxygen at extreme temperatures (around ${2000}^{o}C$) forming Nitric oxide $NO$. Why are such high temperatures required?

1. Oxygen does not react at room temperature.

2. Due to a weak bond between the atoms of nitrogen.

3. Due to a strong bond between the atoms of nitrogen.

4. Due to the inertness of oxygen.

Q. In numericals of vant Hoff factor how to find the value of n ?

Q. How many moles of $N_2$ are needed to produce 18 moles $N{H}_3$ in the reaction?

1. 9
2. 18
3. 3
4. 2
5. 1

Q.

The number of moles in 52g of He is equal to_________

1. 52 moles

2. 1 mole

3. 13 moles

4. 6.022 X 10²³

Q. Four cylinders are filled with 11.2 L of ${\text{H}}_2$, 5 L of ${\text{O}}_2$, 22.4 L of ${\text{N}}_2$ and 8 L of ${\text{Cl}}_2$ gases. Which cylinder contains the maximum number of molecules at STP?

1. The cylinder containing oxygen.
2. The cylinder containing hydrogen.
3. The cylinder containing nitrogen chlorine.
4. The cylinder containing nitrogen.

Q. $1.0$ mol of Fe reacts completely with $0.65$ mol of $O_2$ to give a mixture of only $FeO$ and $F{e}_2{O}_3.$ The mole ratio of ferrous oxide to ferric oxide is:

1. $2:3$
2. $4:3$
3. $1:2$
4. $2:7$

Q. Given below is a balanced chemical reaction for the formation of ammonia.

$N_2\left(g\right)+3H_2\left(g\right)\leftrightharpoons 2N{H}_3\left(g\right)$

Estimate the volume of hydrogen gas required to produce 44.8 litres of $N{H}_3$. (Assume the reaction takes place at STP)

1. 11.2 L
2. 44.8 L
3. 22.4 L
4. 67.2 L

Q. The number of moles of hygrogen molecules required to produce 20 moles of ammonia through Haber's process is:

1. 40
2. 10
3. 30
4. 20

Q. On compete of 2 gm methane $26575$ cals heat is generated . The heat of formation of methane will be (given heat of formation of $C{O}_2$ and $H_2$O are - 97000a and - 68000 cals respectively ):

1. $+20400cals$
2. $+20600cals$
3. $-20400cals$
4. $-2000cals$

Q. The atomic mass of carbon is 12 g and that of oxygen is 16 g. How many grams of carbon contains as many atoms as 50 g of oxygen?

1. 50.0 g
2. 37.5 g
3. 12.1 g
4. 15.9 g

Q. Analyse the reaction given below:

${\text{CaCO}}_3\text{(aq)}$ + ${\text{H}}_2\text{O}\text{(aq)}$ + ${\text{CO}}_2\text{(g)}$ $\to$ ${\text{Ca(HCO}}_3{)}_2\text{(aq)}$

If X is the total number of oxygen atoms and Y is the total number of carbon atoms present in the chemical reaction after balancing, then determine X + Y.

1. 9
2. 12
3. 16
4. 8

Q. Calculate volume of oxygen at STP required to complete the combustion of 8 L of methane.

1. 16

Q. How many moles of iron ($\text{Fe}$) are obtained from iron oxide ( ${\text{Fe}}_2{\text{O}}_3$) by using 15 moles of carbon monoxide ($\text{CO}$)? Use the equation given below.

${\text{Fe}}_2{O}_3\left(s\right)+3\mathrm{CO}\left(g\right)\to 2\mathrm{Fe}\left(s\right)+3{\mathrm{CO}}_2\left(g\right)$

1. 10

Q. How many grams of ${\text{MnO}}_2$ are needed to get 36.2g of ${\text{MnCl}}_2$ from the equation given below?
${\mathrm{MnO}}_2\left(s\right)+4\mathrm{HCl}\left(\mathrm{aq}\right)\to {\mathrm{MnCl}}_2\left(\mathrm{aq}\right)+2H_{2}O\left(l\right)+{\mathrm{Cl}}_2\left(g\right)87g36.5g126g18g71g$

1. 25

Q. Match the following reactants and products with their respective stoichiometry from the given equation.
$N_2\left(g\right)+3H_2\left(g\right)\to 2{\mathrm{NH}}_3\left(g\right)$

1. One
2. Two
3. Three

Q. What mass of ${\text{MnO}}_2$ is required to produce 1.12 litres of chlorine gas at STP acccording to the given equation?

${\text{MnO}}_2\text{(s)}+\text{4HCl}\text{(aq)}\to {\text{MnCl}}_2\text{(aq)}+{\text{2H}}_2\text{O}\text{(l)}+{\text{Cl}}_2\text{(g)}$

Atomic masses of H = 1, Cl = 35.5, Mn = 55, O = 16

1. 4.35 g
2. 6.1 g
3. 25.9 g
4. 25.2 g

Q. How many moles of nitrogen (${\text{N}}_2$) are required to produce 10 moles of ammonia (${\text{NH}}_3$) by reaction with hydrogen (${\text{H}}_2$)?

1. 5

Q.

The mass of 5000 ml of $N{H}_3$ gas at STP is

1. 0.3 g

2. 0.037 g

3. 3.74 g

4. 0.37 g