Question

How do you calculate the molarity of 0.365 g pure HCl gas dissolved in 50 ml of solution, given that the atomic masses are H?

Answer 1

To calculate the molarity of a solute in a solution, you need to know the moles of the solute and the volume of the solution in liters. Here's how you can calculate the molarity of HCl gas in this case:

1. Determine the moles of HCl gas: The molar mass of HCl is approximately 36.5 g/mol (1 g + 35.5 g). Since you have 0.365 g of HCl gas, you can calculate the moles using the formula:

   Moles = Mass / Molar mass Moles = 0.365 g / 36.5 g/mol Moles = 0.01 mol

2. Convert the volume of the solution to liters: You have 50 ml of solution, which needs to be converted to liters. Since 1 liter is equal to 1000 ml, the volume in liters is:

   Volume = 50 ml / 1000 ml/L Volume = 0.05 L

3. Calculate the molarity: Molarity is defined as moles of solute divided by the volume of the solution in liters. Therefore, divide the moles of HCl by the volume:

   Molarity = Moles / Volume Molarity = 0.01 mol / 0.05 L Molarity = 0.2 mol/L

So, the molarity of the HCl gas dissolved in the solution is 0.2 mol/L.