Share all ur chemistry doubts here!!!

[Ameer97]

Solve all your chemistry doubts in p1, 3 or 6 (O-level) by posting it here

 

[Lilly2318]

i usually hv problem in p1 . i get confused btw 2 points

 

[Ameer97]

i usually hv problem in p1 . i get confused btw 2 points

Well chem p1 is little bit tricky and needs alot of practise. U can post any of them though

 

[Ameer97]

How do you rattify the solubility chart?

And can someone post it?

Finally, does someone have a colour chart?

Like, what colour Copper is in in normal state (pink). Not colours of Fe2+, Fe3+, Cu2+, colours of transition metals etc

I dont think u r suppose to learn all the colours of transition metals. Anyhow maybe this can help u out!

Ion

Colour

Copper (II)

Blue

Cobalt (II)

Red

Manganese (II)

Pale pink

Iron (II)

Green

Iron (III)

Orange, yellow or brown

Vanadium (II)

Purple

Vanadium (III)

Green

Vanadium (IV)

Blue

Vanadium (V)

Yellow

 

[Gohar Awais]

I just wanted to ask that I am new to this O level and I just started I will give my exam in 2016 May/June and in my midterm exam I got in chemistry
36/40 in P1 and in P2 I got 65/75 Is this good? I didn't have a P4 , it will be in the final exams. I have two queries:

1.How to find empirical formula of a compound of which they have given molecular structure like 5 Mg atoms and 10 Cl atoms in an arrangements
2.For calculation in moles, if they give volume of gas produced and the mass of reactant used, and find the mol of this gas produced.
Will we use the volume to find the mol or work out by molar ratio by the mass of reactant?

 

[Ameer97]

I just wanted to ask that I am new to this O level and I just started I will give my exam in 2016 May/June and in my midterm exam I got in chemistry
36/40 in P1 and in P2 I got 65/75 Is this good? I didn't have a P4 , it will be in the final exams. I have two queries:

1.How to find empirical formula of a compound of which they have given molecular structure like 5 Mg atoms and 10 Cl atoms in an arrangements
2.For calculation in moles, if they give volume of gas produced and the mass of reactant used, and find the mol of this gas produced.
Will we use the volume to find the mol or work out by molar ratio by the mass of reactant?

1.empirical formula is the simplest molecular formula.
Therefore, u have to simplify no of given atoms:
5Mg and 10 Cl= MgCl2

2. No of mole (for gas at rtp)= volume of gas/volume of gas at rtp (24dm^3)