Question

You are performing an experiment in your lab. To compare with other experiments you need your results to be in moles. During your final step you collect your product and weigh it. You have 600 grams of Mg(H2PO4)2 (magnesium dihydrogen phosphate). How should you enter your results?

Answer 1

Answer: 2.75 moles of magnesium dihydrogen phosphate

Explanation: We have been given 600 gm of Mg(H2PO4)2 .

The molecular mass of Mg(H2PO4)2 is 218 gm.

As it is given that the answer should be in moles so that it can become comparable with other experiments, thus number of moles can be calculated by dividing the given mass by molecular mass of the given salt.

number of moles (n) = given mass(m) / molecular mass of the salt (M)

n= 600 gm / 218 gm = 2.75

Thus 2.75 moles of magnesium dihydrogen phosphate(Mg(H2PO4)2) will be recorded.

Answer 2

To be able to compare the result with other experiments it has to be reported in moles.

number of moles = mass / molecular weight

number of moles of Mg(H₂PO₄)₂ = 600 / 218 = 2.75 moles