Sig Figs

[AllAboutTheLGs]

For absorbance/concentration graph questions, do you have to take into account the sig figs for absorbance when writing your final answer?
For example when given a graph to calculate concentration of X in a sample, if the absorbance value on the y-axis were 2 sig figs, but the concentration in mg/L is to 3 sig figs, do we write the final answer to 2 sig figs eventhough we never actually used the absorbance value in the calculation?

[Kaushik]

Hmmm....from what I've been told its only the least sig figures in your calculations mate.

[AllAboutTheLGs]

Yeah because in one of the VCAA assessment reports it was given to 2 sig figs because the absorbance was to 2 sig figs, but I only used 3 in my calculations. So yeah pretty much the question is would it be 2 sig figs because in order to get the concentration value of 3 sig figs, I had to read off the absorbance value which was 2 sig figs.

[halfbloodprincess]

but if you use molar mass in your calculations, would it be 3 sig fig?

[AllAboutTheLGs]

I'm pretty sure you don't count molar mass in sig figs

[charmanderp]

You do.

[charmanderp]

but if you use molar mass in your calculations, would it be 3 sig fig?

Not unless you had a molar mass greater than 9.9.

[BambooPanda]

On the topic of sig figs, is there a maximum amount of marks you can lose for having the wrong amount of sif figs?

[soccerboi]

On the topic of sig figs, is there a maximum amount of marks you can lose for having the wrong amount of sif figs?

1 mark for the whole paper

[AllAboutTheLGs]

I've never counted molar masses to sig figs zzzz. Omg

[thushan]

I'm pretty sure you don't count molar mass in sig figs

You do.

[Bhootnike]

but only if the question asked you to find the molar mass of something yeah., or if the question stated, showing sig figs for all your calculations?
you don't have to show sig figs in your working i thought, just your final answer?

[thushan]

but only if the question asked you to find the molar mass of something yeah., or if the question stated, showing sig figs for all your calculations?
you don't have to show sig figs in your working i thought, just your final answer?

No, but do it in your working (but use value on cal) to keep track of your accuracies. Particularly important when you're doing back titration calculations and you're mixing subtraction with multiplication/division.