How to find this formula:

  • 1 vote

A sample of rust had the following composition: 25.93 g of iron, 11.11 g of oxygen, 8.33 g of water. Calculate the following and then write the formula for this sample of rust.

a) number of moles of iron atoms, Fe =.....................

b) number of moles of oxygen atoms, O =...................

c) number of moles of water molecules, H2O =.................

d) simplest mole ratio Fe:O:H2O is ..........:............:............

e) formula for this sample of rust is....................

Posted Mon 24th December, 2012 @ 09:45 by Parvathy

1 Answer

  • 0 votes

For a, b and c moles=mass/Mr

D would be working out the empirical formula worked out using the moles you have already calculated

Finally e would be the molecular formula, you work this out by:

1) calculate empirical formula

2) divide molecular mass by empirical formula

3) multiply up the formula

Answered Mon 24th December, 2012 @ 11:10 by Emmiex0x