- Messages
- 1,229
- Reaction score
- 740
- Points
- 123
But why? isnt that it bleaches only litmus paper?
-
We need your support!
We are currently struggling to cover the operational costs of Xtremepapers, as a result we might have to shut this website down. Please donate if we have helped you and help make a difference in other students' lives!
Click here to Donate Now (View Announcement)
Biology; Chemistry; Physics: Post your doubts here!
- Thread starter scouserlfc
- Start date
- Messages
- 86
- Reaction score
- 143
- Points
- 18
Thankyou so much! Can you help me with part k as well? same question
- Messages
- 82
- Reaction score
- 178
- Points
- 43
basically chlorine has bleaching capability which will work on all indicators .. e.g if a universal indicator was used for an alkaline solution and got blue .. we can make it white by passing chlorine
what we calculated in j) is same as what's asked in k) i.e the moles of H2O attached with one mole FeSO4
However when we write values of x , y (these are whole numbers to represent moles) we round them off have you ever seen something like this in a question
: FeSO4. 3.91H2O ....lol .... no right so we round that off.... 3.91 is rounded to 4
http://papers.xtremepapers.com/CIE/...l O Level/Chemistry (5070)/5070_s13_qp_42.pdf
Hey guys in question 9 (b) (i), the marking scheme says Al+3 (1) and Zn +2 (1). Why haven't they mentioned lead? Isn't it correct?
Hey guys in question 9 (b) (i), the marking scheme says Al+3 (1) and Zn +2 (1). Why haven't they mentioned lead? Isn't it correct?
- Messages
- 2,515
- Reaction score
- 4,065
- Points
- 273
Yes i've noticed this too in the past papers,in q's involving situations in which both dissolve in excess NaOH,lead is not mentioned,though it is mentioned in the books.
- Messages
- 657
- Reaction score
- 1,447
- Points
- 143
See Syllabus 2014 Page 29. There is no lead in the cations.
CIE is weird!
http://papers.xtremepapers.com/CIE/...l O Level/Chemistry (5070)/5070_s12_qp_42.pdf
For question 2 (b) (iii), can I write water bath?
For question 2 (b) (iii), can I write water bath?
- Messages
- 1,229
- Reaction score
- 740
- Points
- 123
Yes, Electric Heater can also be used.
- Messages
- 1,229
- Reaction score
- 740
- Points
- 123
can u explain part G of Q8
- Messages
- 316
- Reaction score
- 465
- Points
- 28
can anybody explain these questions?View attachment 41942 View attachment 41943
whats the Mr of air?
View attachment 41944 View attachment 41945
what the purpose of the steel wool + give explanation for all q's
- Messages
- 316
- Reaction score
- 465
- Points
- 28
these as well..View attachment 41946 View attachment 41947
plz clear concepts of redox and reducing agent oxidising agent i always get stuck in redox reactions
View attachment 41948 View attachment 41949
short explanation plzzz
- Messages
- 316
- Reaction score
- 465
- Points
- 28
- Messages
- 510
- Reaction score
- 607
- Points
- 103
Question 5 anyone??????????????
http://papers.xtremepapers.com/CIE/...al O Level/Chemistry (5070)/5070_w05_qp_4.pdf
http://papers.xtremepapers.com/CIE/...al O Level/Chemistry (5070)/5070_w05_qp_4.pdf
- Messages
- 1,229
- Reaction score
- 740
- Points
- 123
whats the difference between volumetric flask and conical flask
See we have NaOH in the flask. HCl is in the burette. According to student 4, more HCl is needed to neutralize the NaOH, which means there is more NaOH. Cleaning the flask with NaOH will result in more NaOH and thus the ans is B
Volumteric is calibrated
- Messages
- 86
- Reaction score
- 143
- Points
- 18
You'll get the moles from f. Find the Mr of FeSO4 only. Use the formula and youll get the mass. No.of moles = Sample mass/ Mr
- Messages
- 82
- Reaction score
- 178
- Points
- 43
Heres a trick on making esters I attached it
MR FeSO4 = 56 + 32 + (16*4) = 152
1 mol FeSO4 =152
for o.o223 : 0.0223*152 =3.39
