[vhpk]

This topic is made in order to provide some good maths about chemistry, not to ask for answer
The first is very easy:
We know that CH₄ has C in sp³, prove that the angle of HCH is 109,5^o

[Borek]

You should start with forum search before posting. I am almost sure I have posted a link to very interesting discussion on the subject.

[vhpk]

Very easy math: Calculate pH of the solution HCl 10^-8M

[AWK]

Very easy math: Calculate pH of the solution HCl 10^-8M

Yes, very easy indeed, but show your attempt

[vhpk]

Very easy math: Calculate pH of the solution HCl 10^-8M

Yes, very easy indeed, but show your attempt

Notice 10^-8M, the solution is too disolved

[vhpk]

Let's find the mistake that I've made in this task:
pH = -lg[H⁺] = -lg[10^-8] = 8
That means the solution is base, but the reality is that it is an acid
Why

[AWK]

Take into account another equilibrium in solusion also, namely Kw=[H₃O⁺][OH^-]. This gives you  a quadratic equation.

[vhpk]

So I understand your idea, thanks a lot
Thus, I want to ask that with H₂SO₄ 98%, we can get its pH over 14. So is this wrong

[AWK]

So I understand your idea, thanks a lot
Thus, I want to ask that with H₂SO₄ 98%, we can get its pH over 14. So is this wrong

Something is wrong in your calculations. Rather pH is below null (negative)

[vhpk]

I'm sorry, the pH will smaller than 0, so is it wrong

[Borek]

I'm sorry, the pH will smaller than 0, so is it wrong

Why?

[vhpk]

Because I have learnt that 0 =< pH =< 14

[Borek]

pH scale