# pls help me, chem calculation

#1
A passenger jet contains 4050 kg of copper wiring. A rock sample contains 1.25% CuFeS2 by mass. Calculate the mass, in tonnes, of rock needed to produce enough copper wire for a passenger jet. (1 tonne = 1000 kg)

i literally have no idea how to work this out, what do i do with the percentage??
0
1 year ago
#2
(Original post by 0603)
A passenger jet contains 4050 kg of copper wiring. A rock sample contains 1.25% CuFeS2 by mass. Calculate the mass, in tonnes, of rock needed to produce enough copper wire for a passenger jet. (1 tonne = 1000 kg)

i literally have no idea how to work this out, what do i do with the percentage??
Hi i can help!! one sec
0
1 year ago
#3
(Original post by 0603)
A passenger jet contains 4050 kg of copper wiring. A rock sample contains 1.25% CuFeS2 by mass. Calculate the mass, in tonnes, of rock needed to produce enough copper wire for a passenger jet. (1 tonne = 1000 kg)

i literally have no idea how to work this out, what do i do with the percentage??
Are u AS AQA chemistry cos i am and i did the q like a week ago,

basically:
convert kg to g
4050kg x 1000 = 4050 x 10^3 g

4050 x 10^3 / 63.5 = 63,779.53 moles of Cu wiring

Mr of CuFeS2 = 183.5

63779.53 x 183.5 = 11703543.76g

11703543.76g / 1 000 000 = 11.70 tonnes = 1.25% rock

therefore

11.70/1.25 x 100 = 936.3 tonnes of rock needed
0
1 year ago
#4
1) so for every 100g of rock, there are 1.25g of CuFeS2. Calculate the proportion by mass that copper would therefore occupy, for every 100g of rock (= Y%)

then do Y% x 1.25 to find mass of Cu in 100g of rock.

2) How to convert 100g into 1 tonne? Multiply by 10000. So for every 1 tonne rock, there are Y% x 1.25 x 10000g Cu.

3) if there are 4050000 g ( = 4.05 T) of Cu in the jet, and (Y% x 1.25 x 10000) g of Cu per 1T of rock, how many Tonnes of rock will you need?
0
#5
(Original post by ammywammy)
Are u AS AQA chemistry cos i am and i did the q like a week ago,

basically:
convert kg to g
4050kg x 1000 = 4050 x 10^3 g

4050 x 10^3 / 63.5 = 63,779.53 moles of Cu wiring

Mr of CuFeS2 = 183.5

63779.53 x 183.5 = 11703543.76g

11703543.76g / 1 000 000 = 11.70 tonnes = 1.25% rock

therefore

11.70/1.25 x 100 = 936.3 tonnes of rock needed
yes i am doing aqa, thank you so much !
0
X

new posts
Back
to top
Latest
My Feed

### Oops, nobody has postedin the last few hours.

Why not re-start the conversation?

see more

### See more of what you like onThe Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

### Poll

Join the discussion

Yes (112)
68.29%
No (34)
20.73%
I didn't use it to prepare (18)
10.98%