Question

Post-lab Questions 1. Calculate the molar mass of H2O and CuSOs (Relative atomic masses). Express your answers in grams per mole to the nearest hundredth (t 0.01 g/mol). Show your work Calculate the mass of water driven off and the mass of copper (II) sulfate formed in your 2. experiment. Express your answers in grams to the nearest hundredth (t 0.01 g). Show your work. pper 3. Calculate the number of moles of copper (II) sulfate present. Express your answer in moles as three significant digits. Show your work 4. Calculate the number of moles of water driven off. Express your answer in moles as three significant digits. Show your work.

Answer 1

1. Sol :-

Relative Molar mass of H₂O = 2 x Atomic mass of H + 1 x Atomic mass of O

= 2 x 1.008 g/mol + 1 x 15.999 g/mol

= 2.016 g/mol + 15.999 g/mol

= 18.01 g/mol

Hence, Molar mass of water at nearest hundred digit = 18.01 g/mol

Similarly,

Relative Molar mass of CuSO₄= 1 x Atomic mass of Cu + 1 x Atomic mass of S + 4 x Atomic mass of O

= 1 x 63.546 g/mol + 1 x 32.065 g/mol + 4 x 15.999 g/mol

= 63.546 g/mol + 32.065 g/mol + 63.996 g/mol

= 159.61 g/mol

Hence, Molar mass of CuSO4 at nearest hundred digit = 159.61 g/mol