GCSE OCR 21st Century Triple Science (CBP1-7) Thread

Yes thats exactly what i put. Is it right?

What was the reagent for D because I didn't think one of them formed a white precipitate and I can check now from a past paper,it was barium chloride wasn't it? Barium chloride (the reagent) and hydrochloric acid don't form a white precipitate I don't think..

Apart from that your points seem solid C seems a deff inate similarity so that's 2 marks I'm guessing if their was a good reason?

I had the pairs the other way around because it said which tests produce the SAME RESULT for BOTH acids: test C produced a white precipitate in HCl but nothing in H2SO4 whereas test D produced nothing in HCl but a white precipitate in H2SO4, therefore the results of those two tests are different for each acid. Tests A and B were similar because their phs would both show they were acidic, and they would both react with magnesium in the same way (salt + hydrogen with fizzing)

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I put AB CD

A was similar because they were both acidic and had low pH's.
B was similar because they both produced hydrogen gas (I think I put hydrogen gas anyway..)
C was dissimilar because it only made a precipitate with one of the acids and not the other, same goes for D.

Silver nitrate and barium chloride I think.

Duck(f). I was kinda maybe sorta hoping to get 50+ and you've ruined that -_- I now believe C is wrong as their is no way they both produce white precipitate

I'm just thinking - these ABCD questions were separated into three marks each, totalling six marks. Do you think that you could get I don't know, C and D wrong but A and B right but for different reasons since the marks have been separated for the full question?

For example:

A and B are similar: A shows different pHs, B shows different rates
C and D aren't similar: Both produce white precipitates

Despite C and D being wrong I think, don't you think they could give you 3/6 for A and B being right?

I think because it was a 6 marker in total, they'd be allot of exceptions like "award mark if incorrect answer but valid justification" kinda like error varied forward

I aim to please

That's just my way of looking at it, but I know there are tonnes of different theories circulating on this thread. Plus, 50+ is a grand target to set

How's everyone feeling for physics?

Much easier content is less and literally follows on from p123 and c456 kinda

How's everyone feeling for physics?

Haha

Your way seems right it went better than my mock in terms of how I felt after and I got in the 50s for that plus my teacher doesn't really like me for chem so it's kind of to prove to her something, I also am starting to like chemistry and it's probs my favourite science-if those even exist

Hmm not too bad but physics is my worst science, I'm just hoping the exam is ok and not horrific! Good luck everyone!!

I never got 50s on mocks I never revised for them but still..

Chem is my favourite too, but I'm not sure why. I guess it just feels the most sciencey out them all. I don't like physics so revising for the 456 is hard..

For p4 and 6 I agree but I gotta do some work on 5, I actually hate circuits! You wired for maths then?

I always revisited night before for mocks I don't rally see the point in trying any more than that as your grade isnt really important but I still do that little bit of revision to make sure I understand everything I think that's why I felt able to start chem revision the day before this time as well for the real thing

True dat. I'm scared of the 456 as the 123 didn't feel good so I gotta make sure this is better!