Question

what is the mass of 11.5 liters of CL2 gas at STP?

Answer 1

At STP, the volume of Cl2 is 22.4 L/mol.

11.5 L Cl2 * (1 mol Cl2/ 22.4 L Cl2)= 115/224 mol Cl2.

115/224 mol Cl2* (70.90 g Cl2/ 1 mol Cl2)= 36.4 g Cl2.

The final answer is 36.4 g Cl2.

Hope this helps~