So I am having trouble with my chemistry.

What I don't understand is what to do when you are predicting the products of a chemical equation, and knowing what its physical state is

for example

Hg (NO3)2 + Na2S -->

I looked at my activity series and Sodium is more reactive than Mercury so I got

Na(NO3) + HgS

then balanced the equation would look like

Hg(NO3)2 + Na2S --> 2Na(NO3) + HgS


so is that right?

am I going in the right direction?

but how do you find out its physical state?

any help would be wonderful!

here is another

H2S04 + Ca(NO3)2 --> ?

Hg(NO3)2 + 2NaS --> 2Na(NO3) + Hg2S

should be the correct balanced equation, though I did a fast job so it might be wrong. Hg is a transition metal so I'm a bit uncertain of the common valence.

But you are on the right track, predicting a chemical reaction is easy, most usually consist of acid base.

Thanks!

There are general physical properties of many chemicals which allow an educated guess, but often it is easiest to go to a reference source to find out the physical property of products in a reaction.

In this case soluble (aq = aqueous solution) reactants form insoluble (s = solid) products:

Hg(NO3)2 (aq) + Na2S (aq)-->2Na(NO3) (aq) + HgS (s)

H2S04 (aq)+ Ca(NO3)2 (aq)--> CaSO4(s) + H2NO3(aq)

help me to do this work balance molecular equations?

___ Fe + ____ S --> ___ FeS