Question

a solid hydrate weighing 2.682 grams was heated to drive off the water. A solid anhydrous residue remained, which weighed 1.420 grams. Calculate the percent of water in the hydrate

Answer 1

The percent of water in the hydrate is found by subtracting the mass of the anhydrous residue from the mass of the hydrate to find the mass of water, then dividing by the original hydrate mass, and multiplying by 100%. The calculation yields a result of approximately 47.05%.

Step-by-step explanation:

To calculate the percent of water in the hydrate, you can follow these steps:

Determine the mass of the water in the hydrate by subtracting the mass of the anhydrous residue from the mass of the hydrate. In this case, the mass of water is 2.682 grams - 1.420 grams = 1.262 grams.

Calculate the percent by mass of water by dividing the mass of water obtained in step 1 by the original mass of the hydrate and then multiplying by 100%. The calculation would be (1.262 grams / 2.682 grams) * 100%.

The final calculation would yield the percent of water in the hydrate. Performing the calculation gives a percentage of approximately 47.05%.

Therefore, the hydrate consists of approximately 47.05% water by mass.

Answer 2

47.05%

Step-by-step explanation:

We are given;

Mass of a solid hydrate = 2.682 grams

Mass of the solid anhydrous residue = 1.420 grams

We are required to determine the percent of water hydrate;

Step 1: Calculating the mass of water in the hydrate

Mass of water = Mass of the solid hydrate - mass of the anhydrous residue

Therefore;

Mass of water = 2.682 g - 1.420 g

= 1.262 g

Step 2: Calculating the percentage of water in the hydrate

% water in the hydrate = (mass of water ÷ mass of the solid hydrate)×100%

Therefore;

% water in the hydrate = (1.262 g ÷ 2.682 g) × 100%

= 47.05%

Hence, the percent water in the hydrate is 47.05%