Chemistry Paper 1 Doubts Here... !

[haochen]

u must look at the equation given and then see the proton transfer as :
acid is a proton donor
base is a proton acceptor
so if once a acid accept proton i will be considered as a base

same goes with the water

hope u understood

 

[JmCullen]

u must look at the equation given and then see the proton transfer as :
acid is a proton donor
base is a proton acceptor
so if once a acid accept proton i will be considered as a base

same goes with the water

hope u understood

yup. i get ur point.. but can i have one example?
i mean, how did you know the protons transfer?
by looking at the eletrons? the charges?

 

[haochen]

by looking at the chrges and i know there is many example but i cant find one coz im busy studying
but if u find one or any of u guyz find one
post it here n ill explain it

 

[JmCullen]

by looking at the chrges and i know there is many example but i cant find one coz im busy studying
but if u find one or any of u guyz find one
post it here n ill explain it

hmm..
let say the water??
acting as a base..

 

[haochen]

maybe in the equation the water is a reactant and when it is converted into a product it accept an electron
so it act like a base.

but i dont think my explaation is correct coz im not sure of the exact question

 

[JmCullen]

maybe in the equation the water is a reactant and when it is converted into a product it accept an electron
so it act like a base.

but i dont think my explaation is correct coz im not sure of the exact question

hahaha..
It's okay~
thanks for your explanation though!

 

[haochen]

ur welcm
but that the general idea

 

[JmCullen]

hey. i have another question..
why the chemical formula of Lead(IV) Oxide is PbO2 and not Pb2O4????

 

[Alpha45]

i think they are both right it is just because PbO2 i more simplified (they divided the equation by 2)

 

[JmCullen]

i think they are both right it is just because PbO2 i more simplified (they divided the equation by 2)

i think that too though. haha

 

[haochen]

Alpha45 is right, u can use both and they just simplified it (like alpha45 said )

 

[JmCullen]

Alpha45 is right, u can use both and they just simplified it (like alpha45 said )

ok.. Thanks!

 

[JmCullen]

hey.. another question alert.. =__=
hmm.
why is silicon dioxide is SiO2 and not SiO4???
while the structure is one silicon bonded to 4 oxygen..

 

[haochen]

Alpha45 is right, u can use both and they just simplified it (like alpha45 said )

ok.. Thanks!

ur welcm

hey.. another question alert.. =__=
hmm.
why is silicon dioxide is SiO2 and not SiO4???
while the structure is one silicon bonded to 4 oxygen..

one thng u didnt count in mind :
hw many bond r there in oxygen with silicon....... 2
so silicon is boned to 4 oxygen and oxygen is bonded to 2 silicon then that make sense
u can also do the cross multiplication
Si4 ------>O2
Si2O4
(simplified)
SiO2

hope u got it
u can also draw the structure to make sure (tetrahedral (like diamond))

 

[JmCullen]

Alpha45 is right, u can use both and they just simplified it (like alpha45 said )

ok.. Thanks!

ur welcm

hey.. another question alert.. =__=
hmm.
why is silicon dioxide is SiO2 and not SiO4???
while the structure is one silicon bonded to 4 oxygen..

one thng u didnt count in mind :
hw many bond r there in oxygen with silicon....... 2
so silicon is boned to 4 oxygen and oxygen is bonded to 2 silicon then that make sense
u can also do the cross multiplication
Si4 ------>O2
Si2O4
(simplified)
SiO2

hope u got it
u can also draw the structure to make sure (tetrahedral (like diamond))

ohya! i can do the cross multiplication.
hahaha.. Thanks a lot!!!!!

 

[haochen]

ur welcm

 

[AStarHunter]

guyz, I have questions (as usual ! )

Okay so here is the first Question. It is kinda difficult to explain so I attached it



Okay 2nd Question is : Which substance can neutralise hydrochloric acid ?

• Ammonia
  Carbon Dioxide
  Litmus Solution

(& why that one and not the others )

3rd Question is also attached --->

Thnx guyz for actually reading this && trying to help annoying me

 

[themathshater]

for da first 1 i thimk its lime
nd da second is aluminum for car bodies cuz its light nd strong
btw can u guyz help me out in 1 Q
its may june 2004 Q NO: 29 abt da dry air stuff
help will be vry much appreciated

 

[haochen]

the first answer :
lime

the second answer is ammonia because it is a base so it can neutralize HCL
while carbon dioxide and litmus solution cant.

the third answer :
Its B


hope it right

for da first 1 i thimk its lime
nd da second is aluminum for car bodies cuz its light nd strong
btw can u guyz help me out in 1 Q
its may june 2004 Q NO: 29 abt da dry air stuff
help will be vry much appreciated

can u post the link ??

 

[haochen]

for da first 1 i thimk its lime
nd da second is aluminum for car bodies cuz its light nd strong
btw can u guyz help me out in 1 Q
its may june 2004 Q NO: 29 abt da dry air stuff
help will be vry much appreciated

u must know the compositon of air then do the following:
first calculate the volume of CO2 and Nitrogen by cross multiplication
(30 * the composition of CO2 in air) / the composition of oxygen in air to find the volume of CO2
do the same with nitrogen
then add up all the volume to get the total volume
which is 150 cm3