# Compunds names and formulas

1. Dec 21, 2009

### sanketm182

i need help understanding compound names and formulas and charges of ions using periodic table

2. Dec 21, 2009

### pr0blumz

Maybe you should post in the Chemistry section.

3. Dec 21, 2009

### Staff: Mentor

Thread moved to Chemistry. Welcome to the PF, sanketm182. What can you tell us about the subject? What courses are you taking now? What kind of introduction to the Periodic Table have you had so far?

4. Jan 12, 2010

### WannabChemist

Perhaps someone could help me out with questions I have relating to this.

How do you determine which chemical takes precedence over others?

For exampe: if there was a mixture of bicarbonate and chlorine and I added sodium, would I have sodium bicarbonate or sodium chloride?

H + Cl + F = HCl + F or HF + Cl?

I hope what i'm asking is clear.

5. Jan 12, 2010

### espen180

As for the sodium question, if the solution reaches saturation, the salt which is least soluble will form.

As for the H,Cl,F question, HCl is a super strong acid and will dissolve completely. HF is a weak acid and will more likely form, but in both cases you are dealing with equilibrium reactions, so the molecules will likely dissolve shortly after forming.

6. Jan 12, 2010

### WannabChemist

Thank you for your reply, but what i'm looking for are general rules to follow (as opposed to specific), perhaps using the periodic table?

An example of a rule (I just made this up off the top of my head): "The molecule with the least electrons will form a compound"

If it were true then flourine would have less electrons so it would make H + F + Cl = HF + Cl.

Obviously i'm just using that rule as an example, but is there some set precedure to working all this out?

Perhaps even a topic reference so I can look it up...

Thanks

7. Jan 12, 2010

### espen180

There are laws which govern reactions, but Chemistry is a lot of casework. You really need to know stuff about the spesific molecules/atoms involved. For example, you might think that H+ and HSO4- in solution will combine to form H2SO4, but in reality very few of protons will do this. The eason is that the equilibrium reaction

$$H_2SO_4(aq)\Longleftrightarrow H^+(aq)+HSO_4^-(aq)\Longleftrightarrow 2H^+(aq) + SO_4^{2-}$$

is strongly weighed to the right (H2SO4 is also a super strong acid).

You really need a table of Ksp, Ka and E0 values to get anywhere with unorganic reactions.

A good place to start is the Wikipedia article on Chemical rections, which lists many reaction types: http://en.wikipedia.org/wiki/Chemical_reaction

8. Jan 12, 2010

### WannabChemist

Thank you for your help, i'll check out and hopefully I can learn some stuff from it.