I need to assign an oxidation number to each of the elements in KMnO4

K
Mn
O4



I also need help with pH

The pH of an acetic acid solution is 4.0. (10n = 1en).

Calculate the [H+]. Moles/liter

What is the [OH-]? Moles/liter

i need to assign an oxidation number to each of the elements in KMnO4

K
Mn
O4

Since there is no charge on KMnO4, the sum of oxidation states is 0

Potassium has the oxidation state (OS) of +1
Manganese has several OS, let's see that later.
Oxygen has the oxidation state of -2

Total OS (let x = OS of Manganese);

1(+1) + x + 4(-2) = 0

Solve for x to find the OS of Mn



i also need help with pH

The pH of an acetic acid solution is 4.0. (10n = 1en).

Calculate the [H+]. Moles/liter

What is the [OH-]? Moles/liter

Use the formula;

pH = - log[H^+]

and to find the [OH-];

[OH^-] + [H^+] = 10^{14}

Note: I've not done pH yet, for the second formula, I'm not so sure.