2002 HSC Q26b) - Simple question (1 Viewer)

[KungPow]

(b) A sample of hard water contains 6 × 10–4 mol L–1 of magnesium carbonate.
Calculate the mass, in mg, of magnesium carbonate in 150 mL of this sample.

Just wanted to know the correct answer.

 

[ben7]

(b) A sample of hard water contains 6 × 10–4 mol L–1 of magnesium carbonate.
Calculate the mass, in mg, of magnesium carbonate in 150 mL of this sample.

Just wanted to know the correct answer.

from exampler answer in standards package 7.5888mg.

 

[Paroissien]

n = 6 x 10-4 * .150
= 9 x 10-5
M = 86
mass = 86 * n
= 0.00774 grams

Damn them taking decimal points

 

[KungPow]

Woot got it right! (may not seem like a big achievement but I always manage to get these questions wrong >_<_

Thanks ben7. Standards package? Is this obtainable?

 

[ben7]

Woot got it right! (may not seem like a big achievement but I always manage to get these questions wrong >_<_

Thanks ben7. Standards package? Is this obtainable?

obtainable from my school library on cd disc, i think they only have it for 2001 and 2002 hsc for there marking standards when they changed the syllabus.

 

[smallcattle]

http://www.boredofstudies.org/mirror/Standards/

 

[ben7]

What! i had no idea these existed on here i though it would like copyrighted or something... they would have helped alot with other subjects... oh well, it happens, at least u know where to go now KungPow

 

[KungPow]

Damn I've never seen those before either. Thank you!