Decimal Places (2 Viewers)

[micuzzo]

sup, just wondering to how many decimal places are we meant to we round off to in chem...ne1 no

thank u

 

[hermand]

three is usually sufficient for anything. although, doing past hsc questions [multiple choice] i've found that they round off to the nearest number.

 

[micuzzo]

i thought it was three...but yeah i always find variation...anyway

thanks

 

[lolokay]

when you add quantities, you take the number of decimal places as the quantity with the least decimal places, when multiplying you use the number of significant figures as the quantity with the least sf's.

just use the rules you're given in chem as to how many dp's/sig figs to put your answer to

 

[Timothy.Siu]

i heard its 4 sig figs

 

[LordPc]

there is a formula, like for log and pH calculations there is a direct sig figs and decimal places ratio

cant remember exactly but it was something like the dp's on the pH is the number of sig figs you use in your answer.

for all other calculations i believe it is up to your own discretion

 

[Trebla]

They're usually not too fussed about this, as long as you make a reasonable approximation. For example, it would be stupid to round off a titre of 28.22 mL to 30mL. A more reasonable one would be 28.2mL. Otherwise, you can follow what lolokay has said, which is the standard approximation procedure in university level science.