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What is the molarity of a solution containing 0.2074 g of calcium hydroxide, Ca(OH)₂, in 40.00 ml of solution?

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Final answer:

To find the molarity of a calcium hydroxide solution, convert the given mass to moles using the molar mass of Ca(OH)2, then divide by the volume in liters. Resulting in a molarity of 0.070 M for the solution.

Step-by-step explanation:

To calculate the molarity of a solution containing calcium hydroxide, Ca(OH)₂, we first need to determine the moles of solute.

Given that the mass of Ca(OH)₂ is 0.2074 g and knowing its molar mass is approximately 74.09 g/mol, we can calculate the number of moles using the formula:

  • moles = mass (g) / molar mass (g/mol)

The moles of Ca(OH)₂ are calculated as follows:

  • moles = 0.2074 g / 74.09 g/mol = 0.0028 mol (rounded to three significant figures)

To find the molarity, we divide the moles of solute by the volume of the solution in liters:

  • molarity (M) = moles of solute / volume of solution (L)

With a solution volume of 40.00 ml or 0.04000 L, we determine the molarity:

  • molarity = 0.0028 mol / 0.04000 L = 0.070 M (rounded to two significant figures)

Therefore, the molarity of the calcium hydroxide solution is 0.070 M.

User Sunil Pandey
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