ATAR Notes: Forum

VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Chemistry => Topic started by: meli001 on June 02, 2011, 10:11:32 pm

Title: 2009 VCAA significant figures...
Post by: meli001 on June 02, 2011, 10:11:32 pm

In Q3 short answer part B, the assessment report rounds off the answer to 2 significant figures but no where in the question is there a measurement with less than 3 signifcant figures.

Am I missing something here? Because I'm pretty sure VCAA don't stuff up their reports... T.T

Oh and how's everyone going with their practise exams?

Title: Re: 2009 VCAA significant figures...
Post by: luken93 on June 02, 2011, 10:24:17 pm

n(HCl) remaining = 0.100 – 0.0200
= 0.080 mol
c(HCl) = 0.080* (M)

The reason for this is that when adding/subtracting, the answer is rounded to the least number of DECIMAL PLACES rather than significant figures, which in this case was 3 decimal places in 0.100

Multiplication/Division = Sig Figs, Adding/subtracting = Decimals

Title: Re: 2009 VCAA significant figures...
Post by: meli001 on June 02, 2011, 10:27:47 pm

Oh really? I didn't know that... thanks a million :)