Chemistry help - balancing equations

Question

I need help with writing and balancing these two equations:

Zinc hydroxide reacts with acetic acid

and

Copper sulphide reacts with acetic acid

thankyou :)

Answer 1

The complete equations are as mentioned in the above answer. I've always found working out the balancing myself to be better, but if you really get stuck on a complicated equation, here's a link to a great site which offers assistance and balances for you:

www.webqc.org/balance.php

Hope this helps :)

Answer 2

My guess that you will form zinc acetate. Zinc is usually a divalent metal (+2 state) and hydroxide is a -1 anion group. Acetic acid can react as an acid to give up a proton and form a salt.

note '_2' means "subscript 2"

Zn(OH)_2 + 2 CH_3COOH --> Zn(OOCCH_3)_2 + 2 H_2O

This says that 1 mol zinc hydroxide reacts with two moles of acetic acid to produce 1 mole of zinc acetate and 2 moles of water.

Note that zinc is complex with two acetate ions, since Zn is +2 and acetate ion is -1.

Answer 3

Zn2+ + 2HC2H3O2(aq) + 2O

Cu(C2H3O2)2(aq) + 2H2S(aq)

Answer 4

Zn(OH)2(s) + 2HC2H3O2(aq) --> Zn(C2H3O2)2(aq) + 2HOH(l)

A better way to represent reactions in aqueous solution is the ionic (and net ionic) equation.  It represents the substances as they "actually" exist.

Zn(OH)2(s) + 2HC2H3O2(aq) --> Zn^2+ + 2C2H3O2- + 2HOH(l)

Interestingly enough, since acetic acid is a weak acid, most of the acetate ions will react with water to make undissociated acetic acid and leave hydroxide ions in solution.

C2H3O2- + HOH(l) <==> HC2H3O2(aq) + OH-

Zn(OH)2(s) + 2HC2H3O2(aq) --> Zn2+ + 2HC2H3O2(aq) + 2OH-

Despite it's odd looks it is consistent with the fact that a solution of the salt, zinc acetate, is basic.

The same would be true for the reaction of copper sulfide (which isn't soluble in water) and acetic acid.

CuS(s) + 2HC2H3O2(aq) --> Cu(C2H3O2)2(aq) + 2H2S(aq)