A 2.914 gram sample of gypsum, a hydrated salt of calcium sulfat, CaSO4, is heated at a temperature greater than 170 degrees Celcius in a crucible until a constant mass is reached. The mass of the anhydrous CaSO4 salt is 2.304 grams. Calculate the percent by mass of water in the hydrated calcium sulfate salt

2.914-2.304 = loss in mass = mass H2O lost.

%H2O = (mass H2O/mass sample)*100 = ?

Note: A more interesting problem is to calculate the formula of the hydrated CaSO4 from these data.

1.88

To calculate the percent by mass of water in the hydrated calcium sulfate salt, we need to determine the mass of water lost during heating.

1. Calculate the mass of water lost:
Mass of hydrated CaSO4 = 2.914 grams
Mass of anhydrous CaSO4 = 2.304 grams

Mass of water lost = Mass of hydrated CaSO4 - Mass of anhydrous CaSO4
= 2.914 g - 2.304 g
= 0.610 grams

2. Calculate the percent by mass of water in the hydrated CaSO4:
Percent by mass of water = (Mass of water lost / Mass of hydrated CaSO4) x 100

Percent by mass of water = (0.610 g / 2.914 g) x 100
= 20.96 %

Therefore, the percent by mass of water in the hydrated calcium sulfate salt is 20.96%.

To calculate the percent by mass of water in the hydrated calcium sulfate salt, we need to find the mass of water and the total mass of the hydrated salt.

First, calculate the mass of water in the hydrated salt:
Mass of water = Mass of hydrated salt - Mass of anhydrous salt
Mass of water = 2.914 g - 2.304 g
Mass of water = 0.610 g

Next, calculate the percent by mass of water:
Percent by mass of water = (Mass of water / Mass of hydrated salt) * 100
Percent by mass of water = (0.610 g / 2.914 g) * 100
Percent by mass of water ≈ 20.97%

Therefore, the percent by mass of water in the hydrated calcium sulfate salt is approximately 20.97%.