Final answer:
To calculate the percentage of water in a hydrated salt, subtract the weight of the anhydrous salt from the weight of the hydrated salt to find the weight of water lost. Then, divide this value by the weight of the hydrated salt and multiply by 100. In the example with a weight of 2.0 grams of hydrated salt reducing to 1.5 grams after heating, the percentage of water is 25%.
Step-by-step explanation:
To calculate the percentage of water in a hydrated salt, we will use the formula:
Percentage of water
= (weight of water lost / weight of hydrated salt) × 100
For this example, let's assume the weight of the hydrated salt is 2.0 grams and after heating it to remove the water, the weight of the anhydrous salt is 1.5 grams.
First, calculate the weight of water lost:
- Weight of hydrated salt = 2.0 g
- Weight of anhydrous salt = 1.5 g
- Weight of water lost = Weight of hydrated salt - Weight of anhydrous salt
- Weight of water lost = 2.0 g - 1.5 g = 0.5 g
Now, use the formula to find the percentage of water:
- Percentage of water = (0.5 g / 2.0 g) × 100
- Percentage of water = 0.25 × 100
- Percentage of water = 25%
Therefore, the percentage of water in the hydrated salt is 25%.