Using states (1 Viewer)

[~ ReNcH ~]

Apart from the ionic substances in a table of solubilities, how do you know what state to use for each substance in a reaction? My teacher said that in some cases, a student would be marked down for using the wrong states. But then, leaving it blank would also lose you marks. If you don't know the state of a substance, what should you do? Even better, how can you determine with confidence what the state of each substance is?

 

[Will Hunting]

There's no one way, man. Over time, though, your exposure to Chem and the reactions involved should foster in you a sense of which states go with what. Often there'll be clues in the questions that enable you to make pretty informed judgments, but, otherwise, try to become as proficient as can be in Chem, in general, and you'll find that your growing familiarity with the subject will breed an almost instinctive knack for deciding upon correct states. Also, try to "understand" what an equation means, rather than just regurgitating a memorised procedure in dealing with it, and you should be able to use common sense to get you through.

 

[~ ReNcH ~]

In a situation where you can't be sure what the state of a substance is, could you be marked down for using incorrect states?

 

[~*HSC 4 life*~]

depends on the marker, but if you did it would be very very small marks lost

 

[Will Hunting]

In a situation where you can't be sure what the state of a substance is, could you be marked down for using incorrect states?

Absolutely. You'd be better off erring on the side of caution and not writing anything than putting something down you're not sure about and risking more for it.

 

[xiao1985]

i would think there will be a set amount allocated to phase...
if u leave it blank u'd lose marks...
believe me, it is quite dearly...

most states however r quite straight forward so u don't need to guess...

 

[Templar]

Absolutely. You'd be better off erring on the side of caution and not writing anything than putting something down you're not sure about and risking more for it.

You'll generally lose marks if you don't put anything down.

In most cases it will only be 2 possible cases, rarely 3, so it's worth the guess anyway.

 

[Will Hunting]

You'll generally lose marks if you don't put anything down.

I wasn't contending that. A misstatement, however, could convince the examiner that you are not conversant with the ideas behind the question, whereupon he/she may hold the error up to a lack of knowledge and choose to penalise more severely.

 

[~ ReNcH ~]

If a question simply asked you to write an equation and was worth 2 marks then I guess you'd get 1 mark for the correct substances and for balancing it, + 1 mark for states.