Biology; Chemistry; Physics: Post your doubts here!

[Qasim Hafeez]

What type of questions come from acid and bases?
Can someone revise that topic with me? pls?

 

[Dark Destination]

In the KMnO4 titrations, what is the color change at end point?
When Iron (II) Sulfate is titrated with KMnO4.

Also, why is Sulfuric acid used in the Electrolysis of water? :/

And, what are the colors of common metals and compounds we should know?

And to how many significant figures should we round our moles answers, in the titration question?

And lastly, how to draw a graph properly?

 

[exploded diper]

does copper only reatcs with conc. nitric acid or all conc. acids'

 

[Dark Destination]

What type of questions come from acid and bases?
Can someone revise that topic with me? pls?

You just need to know general stuff about acids and alkalis and pH.

ATP is about experimental procedures.
You need to know about TITRATION, which is a very important question, that comes everytime. It's always the same, just changed values.
Then you need to know about GRAPHS, the last question is always about graphs.
Then, there are 4-5 MCQ type questions, which are from general topics.

You should know REDOX REACTIONS, ELECTROLYSIS, MOLES, RATE OF REACTION very well. They are the most important topics.

 

[Dark Destination]

does copper only reatcs with conc. nitric acid or all conc. acids'

It reacts with Concentrated Sulfuric acid, too.

 

[Qasim Hafeez]

You just need to know general stuff about acids and alkalis and pH.

ATP is about experimental procedures.
You need to know about TITRATION, which is a very important question, that comes everytime. It's always the same, just changed values.
Then you need to know about GRAPHS, the last question is always about graphs.
Then, there are 4-5 MCQ type questions, which are from general topics.

You should know REDOX REACTIONS, ELECTROLYSIS, MOLES, RATE OF REACTION very well. They are the most important topics.

Not CIE yet, school exams. Chem is so difficult. :'(

 

[Qasim Hafeez]

Dark Destination are you a olevel student?

 

[Laibaaa]

In the KMnO4 titrations, what is the color change at end point?
When Iron (II) Sulfate is titrated with KMnO4.

Also, why is Sulfuric acid used in the Electrolysis of water? :/

And, what are the colors of common metals and compounds we should know?

And to how many significant figures should we round our moles answers, in the titration question?

And lastly, how to draw a graph properly?

1) purple to colourless. I think.
2) It speeds up the reaction by acting as an electrolyte.
3 ans 4) I wanna know the answer too.

 

[Dark Destination]

Not CIE yet, school exams. Chem is so difficult. :'(

So you're freaking out about a school exam.

It's just normal. Not too hard, not to easy. Depends on the type of paper you get.

But you must know the concepts well..

 

[Dark Destination]

Dark Destination are you a olevel student?

Yeah, of course.

 

[exploded diper]

so if we increase concentration , temperature, catalyst, the graph is steeper
and if we increase volume the volume of gas is more so graph is higher..
if we increase concentration does the volume of gas also increases so graph is both steeper and higher ?
and if we decrease volume and increase concentration the graph is steeper but at the same height ....
am i correct????

 

[Qasim Hafeez]

So you're freaking out about a school exam.

It's just normal. Not too hard, not to easy. Depends on the type of paper you get.

But you must know the concepts well..

I got a 'A' last term but this term its so confusing. Specially moles and this acids.bases topics.

 

[Qasim Hafeez]

I feel like I know the topics but questions mess it up.

 

[Laibaaa]

How to prepare Copper (II) Chloride?

 

[Qasim Hafeez]

Yeah, of course.

How to know so much of stuff about chem? How do you prepare?

 

[Dark Destination]

1) purple to colourless. I think.
2) It speeds up the reaction by acting as an electrolyte.
3 ans 4) I wanna know the answer too.

They always ask questions about describe the appearance of magnesium, or zinc. :/ How are we supposed to know this?

 

[Qasim Hafeez]

Any technique or way of learning chemistry and practicing it?

 

[Dark Destination]

How to know so much of stuff about chem? How do you prepare?

Honestly, i have a CIE for Chemistry tomorrow, and today is the first day i have solved Chemistry ATPs.
I just solved 6 Chemistry ATP's in 2 hours. Just now, for the first time ever.
And before that, i skimmed through some redspot atp's..
So it's not much of a big deal, it's just repeated questions with different values. Every paper is identical. With different reagents, different values.

Plus, i have read the book before. So that's how i know.

 

[Laibaaa]

APPEARANCES AND COLOURS:

1. Group 1, 2 metals are white/silvery white. Group 3 metals are shiny grey. Their compounds are white and their solutions are colourless.
2. Zinc is a grey solid, its compounds are white.
3. Lead is a shiny bluish metal, Iron is a shiny blackish solid.
4. Iron (II) salts are green. Iron (III) salts are red-brown.
5. Chlorine is a green gas. Silver chloride and Lead chloride are white.
6. Bromine is a red-brown gas. Silver bromide and Lead bromide are cream coloured.
7. Iodide is a black solid. Its vapours are purple. Silver iodide and lead iodide are yellow.
8. Copper is a pinkish solid. Copper (II) sulphate, Copper (II) hydroxide and Copper (II) nitrate are blue.
9. Copper (II) chloride and Copper (II) carbonate are green.
10. Nitrogen dioxide is a brown gas. Sulphur and Phosphorous are Yellow solids with different flames.

Credits to Saad Mughal.

 

[Dark Destination]

How to prepare Copper (II) Chloride?

By adding Excess copper oxide to Hydrochloric acid, and then filtering out unreacted Copper oxide.
Then, heating the resultant solution, to evaporate of some of the water, and then allowing it to cool. Crystals of copper chloride can then be filtered off, and dried in the folds of a filter paper.