Ask Question
28 April, 08:23

A student has a 2.123 g sample of a hydrated salt. she heats it to drive off all the water. after heating to constant mass, the salt weighs 1.861 g. the anhydrous salt is copper (ii) phosphate. what is the empirical formula of the hydrated salt?

+2
Answers (1)
  1. 28 April, 08:35
    0
    The mass of hydrated salt - 2.123 g

    mass of anhydrous salt - 1.861 g

    mass that has been reduced is the mass of water that has been heated and lost from the compound thereby making the salt anhydrous.

    therefore mass of water lost - 2.123 - 1.861 = 0.262 g

    number of moles of water lost - 0.262 g / 18 g/mol = 0.0146 mol

    number of moles of salt - 1.861 g / 380.6 g/mol = 0.00490 mol

    molar ratio of moles of water to moles of salt

    molar ratio = 0.146 mol / 0.00490 mol = 2.98 rounded off to 3

    for every 1 mol of salt there are 3 moles of water

    therefore empirical formula - Cu₃ (PO₄) ₂.3H₂O
Know the Answer?
Not Sure About the Answer?
Find an answer to your question ✅ “A student has a 2.123 g sample of a hydrated salt. she heats it to drive off all the water. after heating to constant mass, the salt weighs ...” in 📘 Chemistry if you're in doubt about the correctness of the answers or there's no answer, then try to use the smart search and find answers to the similar questions.
Search for Other Answers