Question

calculate mass of 2.8 litres of Co2 . [C=12 , O=16]

Answer 1

Mass of 1 mole CO2=44gm
1 mole=22.4L
therefore, mass of 22.4L=44gm
Mass of 2.8L=
$\frac{2.8}{22.4} \times 44 = \frac{44}{8}$

Answer 2

Answer: 5.5 grams

Explanation:

According to avogadro's law, 1 mole of every substance weighs equal to its molecular mass ,contains avogadro's number $6.023\times 10^{23}$ of particles and occupy 22.4 L at STP.

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given volume}}{\text{Molar volume}}=\frac{2.8L}{22.4L}=0.125$

1 mole of $CO_2$ weigh = 44 g

0.125 moles of $CO_2$ weigh = $\frac{44}{1}\times 0.125=5.5grams$

Thus mass of 2.8 litres of $CO_2$ is 5.5 grams