Your value probably does not match the actual value for the hydrate. Use the following formula to calculate the percent error for the experiment. Remember to report an absolute value. [2]

Question

1. Use your data to calculate the number of water molecules to two decimal places. [4]

Moles of water H2O 11.38- 7.28 = 4.1g 

Moles of anyhydrate ( CuSO4)= 7.28/159.62 = 0.0456 moles of copper sulfate

n = m/M

m = 4.1g, M = 18.02g

n = 4.1/ 18.02 = 0.227 moles of water

 

molecules of water 0.227(6.02 x 10^23)

                                          = 1.37 x 10^23

Answer this:

1. Your value probably does not match the actual value for the hydrate. Use the following formula to calculate the percent error for the experiment. Remember to report an absolute value. [2]

Percent error = (theoretical – experimental) x 100%

    theoretical

Answer 1

The empirical formula of this hydrate is CuSO₄•5H₂O, from your experimental data you got for every

1 mole of CuSO₄ : 4.987 moles of H₂O. This means your experimental error is very small as if you measured 4.104g of H₂O instead of 4.1 it would have been perfect, when you calculate the number of water molecules you theoretically should yield if rounded as specified would be exactly the same as you measured experimentally 1.37 x 10²³. If we used the mass of water to calculate the percent error:

4.104 - 4.10 ⁄ 4.104 = 9.7465 x 10^-4 x 100 = 0.97% error