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[natsume hyuga]

f

when so2 is dissolved in water as follows
SO2 + H2O --> H2SO3
it gives sulphurus acid which turns blue litmus paper red .. but what im not getting is why the pH above 7 !!

forget it , its wrong in the mark scheme..

 

[saroooor]

lsn to cut short when they say 2 atoms of X it means 2X and NOT X^2+ as well as when they say 3 atoms of Y it means 3Y and NOT Y^3- get it?

Yes !

 

[Razo513]

f
forget it , its wrong in the mark scheme..

yes it's C im 100% sure

 

[Evangeline]

LOL

ameen! i hope we all get A* please pray for me sisters.

 

[areebaization]

ameen! i hope we all get A* please pray for me sisters.

ameen u will get A*s too

 

[natsume hyuga]

wait guys water has an effect on the pH of the acid. 2003 mayjune chem :
21 Water is added to a test-tube containing dilute sulphuric acid of pH 4.
What could be the pH of the resulting solution?
A 8
B 6
C 4
D 2
answer is B!

 

[ZainH]

wait guys water has an effect on the pH of the acid. 2003 mayjune chem :
21 Water is added to a test-tube containing dilute sulphuric acid of pH 4.
What could be the pH of the resulting solution?
A 8
B 6
C 4
D 2
answer is B!

Since the pH of water is 7 (Neutral) and the pH of sulfuric acid is 4, it's sorta obvious the pH will not decrease. So you can eliminate options C and D. Now your left with a pH of 8 or a pH of 6.. the water will not turn the solution akaline , it will just turn it into a weaker acidic solution , so your answer is B. pH6.

 

[Skynox]

wait guys water has an effect on the pH of the acid. 2003 mayjune chem :
21 Water is added to a test-tube containing dilute sulphuric acid of pH 4.
What could be the pH of the resulting solution?
A 8
B 6
C 4
D 2
answer is B!

The PH range changes within the acidity,water can't move HCL from ph 2 to 11 for example.

 

[natsume hyuga]

Since the pH of water is 7 (Neutral) and the pH of sulfuric acid is 4, it's sorta obvious the pH will not decrease. So you can eliminate options C and D. Now your left with a pH of 8 or a pH of 6.. the water will not turn the solution akaline , it will just turn it into a weaker acidic solution , so your answer is B. pH6.

ah yes yes yes now i get it. Its not the water that has an effect on the acid, but the acid that has an effect on the water.... wow im stupid

 

[ZainH]

ah yes yes yes now i get it. Its not the water that has an effect on the acid, but the acid that has an effect on the water.... wow im stupid

We all have our blonde moments ..

 

[natsume hyuga]

hahah blonde jokes

We all have our blonde moments ..

 

[svenas]

yes it's C im 100% sure

yes ryt!!

 

[natsume hyuga]

guys u know the q abt the galvanised roof?the answer in the mark scheme shows that zinc is also included in the composititon, but in the previous discussion we had, we said the opposite :s oct nov 2004

 

[Skynox]

guys u know the q abt the galvanised roof?the answer in the mark scheme shows that zinc is also included in the composititon, but in the previous discussion we had, we said the opposite :s oct nov 2004

Question number?

 

[natsume hyuga]

.32

Question number?

 

[Skynox]

.32

Galvanizing occurs to steel ob'ects,
Steel mainly is iron/carbon so a galvanized roof contains iron/carbon and very little coat of zinc..

Galvanizing is : applying a layer of zinc on the stell structure either by electroplating or dipping in molten zinc

 

[natsume hyuga]

why isnt hydrogen part of the composition of clean air?

 

[Skynox]

why isnt hydrogen part of the composition of clean air?

Hydrogen is flammable so imagine hydrogen being a part of air..

 

[natsume hyuga]

http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Chemistry (0620)/0620_s06_qp_1.pdf
whats the concept behind question 35? the answer is C

 

[natsume hyuga]

Hydrogen is flammable so imagine hydrogen being a part of air..

okkay