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

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

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

AS Chem MOLE QUESTIONHELP!

Q. Which of the following letters corresponds to the number of moles of each element in 53g or Na2CO3 (Mr: 106)

*A: Na 0.5 / C 0.5/ O 0.5
*B: Na 1 / C 0.5/ O 3
*C Na 1/ C 0.5/ O 1.5

Mark scheme answer is C but I need an explanation please

Original post by valbrechts

Q. Which of the following letters corresponds to the number of moles of each element in 53g or Na2CO3 (Mr: 106)

*A: Na 0.5 / C 0.5/ O 0.5
*B: Na 1 / C 0.5/ O 3
*C Na 1/ C 0.5/ O 1.5

Mark scheme answer is C but I need an explanation please

First calculate the number of moles of the compound: 53/106 = 0.5 moles of Na2CO3

Remember a mole is just a number. So if one molecule contains 2 sodium atoms, then 0.5 moles should contain 2*0.5 = 1 mole of sodium atoms.

Can you do the rest now? :smile:

:smile:

does anyone know part 3 (a) (iii)? I don't know why they divided it? thanks

Original post by ruchitax

does anyone know part 3 (a) (iii)? I don't know why they divided it? thanks

Post the question

Original post by Squishy•

Post the question

http://filestore.aqa.org.uk/subjects/AQA-CHEM1-W-QP-JUN10.PDF
forgot to send the link. that is the paper.

Quick Reply

Latest

Trending

Trending

Articles for you

Waiting for uni offers: how to keep your head

Waiting for uni offers: how to keep your head

What should you do if you don't get a place in student halls?

What should you do if you don't get a place in student halls?

How student finance actually works

How student finance actually works

What it’s really like qualifying as a solicitor through the SQE

What it’s really like qualifying as a solicitor through the SQE