Final answer:
The volume occupied by 9.45 g of C2H2 at STP is approximately 8.12672 liters, using the molar mass of C2H2 and the molar volume of a gas at STP.
Step-by-step explanation:
To calculate the volume occupied by 9.45 g of C2H2 (acetylene) at STP (standard temperature and pressure), we can use the concept of molar volume. The molar mass of C2H2 is 26.04 g/mol (12.01 g/mol for carbon times 2 plus 1.008 g/mol for hydrogen times 2). First, we convert the mass of acetylene to moles:
- (9.45 g C2H2) / (26.04 g/mol) = 0.3628 moles C2H2
At STP, one mole of a gas occupies 22.4 liters. Hence, the volume occupied by 0.3628 moles of C2H2 gas can be calculated as:
(0.3628 moles) × (22.4 L/mol) = 8.12672 L
Therefore, 9.45 g of C2H2 gas occupies approximately 8.12672 L at STP.