If Avogadro number \(N_{A}\), is changed from$\mathrm{}$ \(6 . 022 \times \left(10\right)^{23}\)\(\text{mol}^{- 1}\) to \(6 . 022 \times \left(10\right)^{20} ~\text{mol}^{- 1}\) this would change the:

A mixture of gases contains H₂ and O₂ gases in the ratio of 1 : 4 (w/w). The molar ratio of the two gases in the mixture will be:

When 22.4 litres of H₂(g) is mixed with 11.2 litres of Cl₂(g), both at STP, the moles of HCl(g) formed are equal to:

1. 1 mol of HCl(g)
2. 2 mol of HCl(g)
3. 0.5 mol of HCl(g)
4. 1.5 mol of HCl(g)

When \(1.0\text{ g}\) of magnesium (\(\text{Mg}\)) is reacted with \(0.56\text{ g}\) of oxygen (\(\text{O}_2\)) in a closed container, determine the reactant left in excess and calculate the mass of the excess reactant remaining after the reaction is complete: (At. wt. Mg = 24; O = 16)

Which of the following has the greatest number of molecules?

1. 64 g SO₂ 

2. 44 g CO₂

3. 48 g O₃ 

4. 8 g H₂

The number of atoms in 0.1 mole of a triatomic gas is (N_A= 6.02 x 10²³ mol^-1):

1. $6.026\times {10}^{22}$

2. $1.806\times {10}^{23}$

3. $3.600\times {10}^{23}$

4. $1.800\times {10}^{22}$