Year 12s: what will be the first way you research your future options? >>

Water of Crystallisation question! please help!

Calculate how much Zn(NO₃)₂ · 6H₂O (in grams) is needed to prepare 0.5L of 1000 mg Zn/ L solution knowing the following data: Molar mass of Zn is 65.38 g/molMolar mass of Zn(NO₃)₂ · 6H₂O is 297.49 g /mol.Your answer must be given with 3 digits, for example X.YZ g

Please help! very confusing question! :frown:

Reply 1

username986184

Original post by steffff

Work out:

1) Mass of zinc you need for 0.5L
2) Number of moles of zinc that equates to. this will be the number of moles of hydrated compound needed.
3) Mass of hydrated salt needed.

All done with moles = mass / Mr (or Ar)

Reply 2

steffff

thank you for your reply.
I understand how to obtain the mass at the end from the formula, however I dont understand how to get the moles from the 0.5L of 1000mg Zn/L?

Reply 3

username986184

Original post by steffff

thank you for your reply.
I understand how to obtain the mass at the end from the formula, however I dont understand how to get the moles from the 0.5L of 1000mg Zn/L?

If 1L contains 1000mg (1g) how much does 0.5L contain?

Quick Reply

Latest

Articles for you

What your body does to cope with stress in exams

Life lessons university will teach you

What university is really like

Revising with ADHD

Water of Crystallisation question! please help!

Quick Reply

Related discussions

Latest

Trending

Trending

Articles for you