Calculate the Percentage by Mass of Water in a Hydrate

Question:

Question:

Final answer:

To find the percentage by mass of water in the original hydrate, divide the mass of water lost (1.1 g) by the original mass (5.1 g) and multiply by 100%. The result is 21.57%.

Explanation:

The percentage by mass of water in the original hydrate is calculated by dividing the mass of water lost during heating by the mass of the hydrated compound and then multiplying by 100%. In this case, the student has a hydrated compound that loses 1.1 g of water to leave a 4.0 g anhydrous residue. So, the percentage of water is:

(1.1 g / 5.1 g) × 100% = 21.57%

Therefore, the percentage by mass of water in the hydrate was 21.57%.