If 4.02 grams of a hydrate of magnesium sulfate loses 2.06 grams of water when heated, what is the formula for the hydrate
mass H2O = 2.06
mass salt = 4.02-2.06 = 1.96
mols H2O = 2.06/18 = about 0.114
mols MgSO4 = 1.96/120.4 = 0.0163
0.114/0.0163 = 7.00; therefore, the formula is
MgSO4.7H2O
Well, if you really want to know, I can give you a formula for your hydrate: H2O + MgSO4. But don't trust me on this, I'm just a clown bot. Maybe you should double-check with a chemistry expert, just to be on the safe side.
To determine the formula for the hydrate, we need to calculate the mole ratio between the anhydrous salt and the water.
Step 1: Calculate the number of moles of anhydrous salt.
To do this, divide the mass of the anhydrous salt by its molar mass.
Molar mass of magnesium sulfate (MgSO4) = 24.31 g/mol (Mg) + 32.06 g/mol (S) + 4 * 16.00 g/mol (O) = 120.37 g/mol
Number of moles of anhydrous salt = 4.02 g / 120.37 g/mol
Step 2: Calculate the number of moles of water lost.
To do this, divide the mass of water lost by its molar mass.
Molar mass of water (H2O) = 2 * 1.01 g/mol (H) + 16.00 g/mol (O) = 18.02 g/mol
Number of moles of water lost = 2.06 g / 18.02 g/mol
Step 3: Determine the mole ratio between the anhydrous salt and the water.
Divide the moles of anhydrous salt by the moles of water lost.
Mole ratio = moles of anhydrous salt / moles of water lost
Step 4: Simplify the mole ratio (if necessary) to obtain whole number ratios.
The simplified mole ratio will give us the formula for the hydrate.
By going through these steps, you can determine the formula for the hydrate.
To find the formula for the hydrate given the mass of the hydrate and the mass of water lost, we need to use the concept of the molar ratio.
The molar ratio is the ratio of moles between different substances in a chemical equation. In this case, we want to determine the ratio of moles between the hydrate (MgSO₄·xH₂O) and water (H₂O) using the given mass values.
To start, we need to find the number of moles of magnesium sulfate (MgSO₄) and water (H₂O) separately. We can calculate the moles using the molar mass and the given mass.
The molar mass of magnesium sulfate (MgSO₄) is the sum of the atomic masses of each element:
Mg: 24.31 g/mol
S: 32.07 g/mol
O (4 atoms): 16.00 g/mol x 4 = 64.00 g/mol
Total molar mass of MgSO₄ = 24.31 + 32.07 + 64.00 = 120.38 g/mol.
Now let's calculate the number of moles of magnesium sulfate (MgSO₄):
moles of MgSO₄ = mass of compound / molar mass of compound
= 4.02 g / 120.38 g/mol
≈ 0.03344 mol
Next, let's calculate the number of moles of water (H₂O):
moles of H₂O = mass of water / molar mass of water
= 2.06 g / 18.02 g/mol
≈ 0.1142 mol
Now, we need to find the ratio between moles of magnesium sulfate and moles of water by dividing the moles of water by the moles of magnesium sulfate:
moles of H₂O / moles of MgSO₄
So, the ratio is:
0.1142 mol / 0.03344 mol
Simplifying, we get:
3.41 mol H₂O / 1 mol MgSO₄
This means that there are approximately 3.41 moles of water for every 1 mole of magnesium sulfate.
To determine the ratio of water (H₂O) in the formula for the hydrate, we need to find the simplest whole number ratio. In this case, we have 3.41 moles of water for every 1 mole of magnesium sulfate.
Thus, the formula for the hydrate is MgSO₄·3.41H₂O.
Keep in mind that we rounded the ratio to two decimal places (3.41) for simplicity, but the actual value may be a more precise decimal.