Biology; Chemistry; Physics: Post your doubts here!

[SalmanPakRocks]

Well I have it with me but the thing is I can't understand the defination written by Charles Chew so I was hoping for an alternative kind of defination. I mean some change in words which could make me understand it.

 

[XPFMember]

I need help in Thermal Physics (O levels).

As-salam-o-alaikum!

1)Heat Capacity:

• The heat capacity C of a substance is the amount of heat required to change its temperature by one degree.

2) Specific Heat Capacity:

• It is the amount of heat required to change the temperature of one unit of mass of a substance by one degree.

3) Latent Heat of Fusion:

• It is the energy required to change a substance from solid to liquid without change in temperature.

4) Specific Latent Heat of Fusion:

• The amount of energy per kg (unit mass) required to change from the solid state to the liquid state without change in temperature.

5) Latent Heat of Vaporisation:

• It is the energy required to change a substance from liquid to gas without change in temperature.

6) Specific Latent Heat of Vaporisation:

• The amount of energy per kg (unit mass) required to change a substance from liquid to gas without change in temperature.

Remember for change in temperature => E= mcΔθ where c is the specific heat capacity, and Δθ is the change in temperature.

and for change of state E=mL where L is the specific latent heat

 

[SalmanPakRocks]

^^ Jazaka'Allah for ur help!

 

[SalmanPakRocks]

Assalam o likum
Well I wanted to ask those who have already appeared in the Physics that what topics are usually tested in Physics ATP?

 

[Silent Hunter]

depends.... look through the past papers..... mostly the following:

-pendulum one
-heat capacity one
-electricity one
-mechanics
-some general questions about accuracy etc

etc etc

 

[XPFMember]

As-salam-o-alaikum!

^^ Jazaka'Allah for ur help!

Wa eyakum!

 

[GetSomeLife]

So...did anyone figure out da question???

 

[Silent Hunter]

which question???????????

 

[GetSomeLife]

When water reacts with acid HCl, it forms H3O and Chlorine
But wat happens wen it reacts wid Sulphuric acid?????

 

[XPFMember]

Assalamoalaikum!!

H2SO4 + 2H2O => 2H3O^+ + SO4^2-

?? isnt it this?

Because water acts as a base with acids and vice versa...andbased on this I've given this eqn?!

 

[SalmanPakRocks]

Assalamoalaikum!!

H2SO4 + 2H2O => 2H3O^+ + SO4^2-

?? isnt it this?

Because water acts as a base with acids and vice versa...andbased on this I've given this eqn?!

hmmm
how did u do it?

 

[XPFMember]

As-salam-o-alaikum!

Well acids are proton donor, bases are proton acceptors!

H2SO4 will give away it's hydrogen forming sulfate ions

H2O will accept these protons forming hydronium ions = H3O^+

 

[SalmanPakRocks]

oh. Jazaka'Allah!

 

[XPFMember]

oh. Jazaka'Allah!

Aoa!

wa eyakum..

hope u got it...

btw i told it with my knowledge....that's what seems to be correct to me!

 

[SalmanPakRocks]

Actually I didn't knew that either! perhaps we aren't taught that in O levels still I will try to gain more information regarding it.

 

[Silent Hunter]

yes... i did not study it in olevels.but you will know about it in AS levels

 

[XPFMember]

Actually I didn't knew that either! perhaps we aren't taught that in O levels still I will try to gain more information regarding it.

assalamoalaikum!!

strange! I studied that in IGCSE! not in A levels!

 

[SalmanPakRocks]

ok so how can we apply any theory regarding it here? I mean its an O level question.
yet i never ever ecountered such a question in the past papers.

 

[XPFMember]

IGCSE is equivalent to O levels!

You just need to know that water can act as acid as well as a base! Accepts Hydrogen ion forming H3O^+

 

[SalmanPakRocks]

oh ok! thanks.