Question

A scientist makes a solution that contains 22.0 grams of hydrogen chloride gas, HC(g), in 100. grams of water, H2O(I), at 20. °C. This process is represented by the balanced equation below.

HCI(g) -- H+(aq) + CI (aq)

Calculate the molarity of the solution.

Answer 1

To find the molarity of a hydrogen chloride solution, convert the mass of HCl to moles using its molar mass (36.46 g/mol) and then divide by the volume of the solution in liters. In this case, the solution has a molarity of 7.731 M.

Step-by-step explanation:

To calculate the molarity of the solution containing hydrogen chloride gas (HCl) in water, we must first convert the mass of HCl to moles. Since the molar mass of HCl is 36.46 g/mol, we use this as a conversion factor:

22.0 g HCl × (1 mol HCl / 36.46 g HCl) = 0.603 moles HCl

Next, since the solution's total mass is 100. grams and HCl's mass is 22.0 grams, the mass of water is 100.0 g - 22.0 g = 78.0 g.

To find the volume of water, we use the density of water which is 1 g/mL at 20 °C. Therefore, the volume of water is 78.0 mL or 0.0780 liters.

Now, we can calculate the molarity (M), which is moles of solute per liter of solution:

Molarity = 0.603 moles HCl / 0.0780 liters

= 7.731 M

This is the molarity of the hydrogen chloride solution at 20 °C.