Question

A gas cylinder can hold 1 kg of hydrogen at room temperature and pressure. (a) Find the mole of Hydrogen present. (b) What mass of carbon dioxide can it hold under similar conditions of temperature and pressure. (c) if the number of molecules in hydrogen of cylinder is X, calculate the number of carbon dioxide molecules in the cylinder.

Answer 1

Looks like the first one may be a 1000 moles

Answer 2

Answer:

a) 500 moles

b)22 kg

c) X molecules of $CO_2$

Explanation: a) To calculate the moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text {Molar mass}}$

$\text{Number of moles of Hydrogen}=\frac{1000g}{2g/mol}=500moles$

b) Equal volume of gases contain equal number of molecules at similar conditions of temperature and pressure.

Thus moles of $CO_2$ = moles of $H_2$ = 200 moles

Mass of $CO_2={\text {number of moles}}\times {\text {Molar mass}}$

Mass of $CO_2=500\times 44g/mol=22000g=22kg$

c) According to avogadro's law, 1 mole of every gas occupies 22.4 Liters at STP and contains avogadro's number $6.023\times 10^{23}$ of particles.

Similar moles of gases contain similar number of molecules.

Thus if number of molecules of hydrogen is X, the molecules of $CO_2$ will also be X.