I need help with this lab.
Write the equation for the decomposition of the hydrate, CuSO4*XH2O.
Mass of crucible and hydrate: 93.000g
Mass of crucible and pure salt: 91.196g
I need to calculate the following:
1. mass of water in hydrate sample(g)
2. number of moles of water in the sample
3. mass of pure salt in the sample(g)
4. number of moles of salt in the sample
5. molar ratio of water to salt in the sample
From your calculations what is the empirical formula of copper sulfate hydrate?
I cant figure out how to get the emperical formula??????
If you have no more data than this I can't figure it out either.
93.000 g = mass xble + hydrate
91.196 g = mass xble + salt
---------
1.804g = mass water lost
mols H2O = 1.804/18 = 0.100
But this is as far as you can go.
You need the mass of the crucible, then you can figure the mass of the CuSO4.
mols CuSO4 = grams/molar mass.
To determine the empirical formula of copper sulfate hydrate, we need to find the ratio between the moles of copper sulfate and moles of water in the sample.
Let's follow these steps:
1. Calculate the mass of water in the hydrate sample:
Mass of water = Mass of crucible and hydrate - Mass of crucible and pure salt
Mass of water = 93.000g - 91.196g = 1.804g
2. Calculate the number of moles of water in the sample:
Moles of water = Mass of water / molar mass of water
The molar mass of water (H2O) = 2(1.008g/mol) + 16.00g/mol = 18.02g/mol
Moles of water = 1.804g / 18.02g/mol = 0.100mol
3. Calculate the mass of pure salt in the sample:
Mass of pure salt = Mass of crucible and pure salt - Mass of crucible
Mass of pure salt = 91.196g - 91.000g = 0.196g
4. Calculate the number of moles of salt in the sample:
Moles of salt = Mass of salt / molar mass of salt
Since the molar mass of copper sulfate (CuSO4) is not given, let's calculate it:
Molar mass of Cu = 63.55g/mol
Molar mass of S = 32.07g/mol
Molar mass of O = 16.00g/mol (4 oxygen atoms in CuSO4)
Molar mass of copper sulfate (CuSO4) = 63.55g/mol + 32.07g/mol + 16.00g/mol(4) = 159.61g/mol
Moles of salt = 0.196g / 159.61g/mol ≈ 0.00123mol
5. Calculate the molar ratio of water to salt:
Divide the moles of water by the moles of salt:
Molar ratio = Moles of water / Moles of salt
Molar ratio ≈ 0.100mol / 0.00123mol ≈ 81.30
From the molar ratio, we can round it to the nearest whole number, which is 81. The empirical formula of copper sulfate hydrate is CuSO4·81H2O.
To determine the empirical formula of copper sulfate hydrate, we need to use the given information and perform some calculations. Here's how you can find the empirical formula step by step:
1. Start by calculating the mass of water in the hydrate sample:
Mass of water = Mass of crucible and hydrate - Mass of crucible and pure salt
Mass of water = 93.000 g - 91.196 g = 1.804 g
2. Next, find the number of moles of water in the sample using the molar mass of water (H2O):
Molar mass of water (H2O) = 2(1.008 g/mol) + 16.00 g/mol = 18.02 g/mol
Number of moles of water = Mass of water / Molar mass of water
Number of moles of water = 1.804 g / 18.02 g/mol = 0.100 mol
3. Determine the mass of pure salt in the sample:
Mass of pure salt = Mass of crucible and pure salt - Mass of crucible
Mass of pure salt = 91.196 g - 93.000 g = -1.804 g
(Note: A negative mass indicates that there was an error in the calculations or measurements. Please recheck your values and ensure that the mass of pure salt is positive.)
4. Calculate the number of moles of salt in the sample:
To determine the number of moles of salt in the sample, we need to know the molar mass of copper sulfate (CuSO4). Once we have the molar mass, we can use the following formula:
Number of moles of salt = Mass of pure salt / Molar mass of copper sulfate
5. Find the molar ratio of water to salt in the sample:
The molar ratio can be determined by dividing the moles of water by the moles of salt:
Molar ratio = Moles of water / Moles of salt
6. Finally, deduce the empirical formula of copper sulfate hydrate:
The empirical formula represents the simplest whole number ratio of atoms in a compound. To find the empirical formula, we need to know the molar ratio of water to salt. For example, if the molar ratio is 1:2, the empirical formula would be CuSO4•2H2O.
Please double-check your values and calculations to obtain the correct mass of pure salt.