Error in answer to HSC 2003 Q5? (1 Viewer)

[Trebla]

Have a look at 2003 HSC Question 5. What do you think the answer is? According to the Notes from the Marking Centre and the Online Multiple Choice test, it is D, whereas according to Success One and myself, it is A. I don't understand why D would be correct. There must be some error in there.

 

[izzy88]

see i actually would have said D....because u are measuring dissolved solids u would have to filter out the undissolved solids before evaporating as otherwise u would be left with both undissolved and dissolved solids to measure....not just the ones that had been dissolved

 

[GaganDeep]

it's D, it's muddy, get rid of suspended solids first.

 

[Trebla]

In Success One it reasons that Filtration (S) cannot be used to separate dissolved substances and a separating funnel (R) is used to separate immiscible liquids.
Given that this comes from the Science Teachers' Association, does that mean that this is an error in the book?

 

[Nodice]

The process you use it you filter off the other stuff first so that you can actually evaporate stuff out. No use evaporating if youve got a big pile of crud in there.

 

[Naylyn]

I don't see how they could have possibally got A for that question, their reasoning is quite flawed:
"Filtration (S) cannot be used to separate dissolved substances and a separating funnel (R) is used to separate liquids"

However to find the total dissolved solid you must first remove the undissolved solids..

Even the best teachers make mistakes.

 

[speedie]

man, success one sux. theres so many more really crappy errors in the book. i really dont trust their answers. anyway, its d for sure. (sometimes there is also alot of typo's in success one)