write HBr, HF,Sr,NH4OH, AgNO3, Ag2SO4 substance as it exists in aqueous solution?

Answer 1

1) HBr(aq) --> H+(aq) + Br-(aq)
2) HF(aq) --> H+(aq) + F-(aq)

ref: http://en.wikipedia.org/wiki/Hydrofluoric_acid

3) Sr(s)
4) AgNO3(aq) --> Ag+(aq) + NO3-(aq)
5) Ag2SO4(aq) --> 2Ag+(aq) + SO4-2(aq)

ref: http://en.wikipedia.org/wiki/Silver_sulfate

Answer 2

Both of the above answerers have some correct responses, but:
1. HF is a weak acid, so it is best to write HF(aq) as the majority product
2. NH4OH does not exist in any great concentration, because NH3 is a very weak alkali. It is better to write NH3(aq) as the majority product.
3. Sr is a very reactive metal, and it is impossible for it to remain in solution as the metal. The species in solution would be Sr2+(aq).

Answer 3

H+(aq) + Br-(aq)
HF(aq) does not dissassociate
Sr(s)
NH4+(aq) + OH-(aq)
Ag+(aq) + NO3-(aq)
Either Ag2SO4(s) or 2Ag+(aq) + SO4 2-(aq) I don't have a chemistry book handy to check if the silver sulfate is soluble or not in water, but there should be a chart in the book