I need help on a chemistry problem in the practice assesment...

[Distraught_Concerned]

Ca + H2SO4

Which of the following statements correctly describes the outcome of the reaction above?

A. Calcium is oxidized to Ca2+

B. Sulfuric acid is decomosed to hydrogen sulfide.

C. Sulfuric acid is neutralized to calcium sulfate.

D. Hydrogen is oxidized to hydrogen gas.

The answer is A. I'm trying to rationalize an answer, but I just can't. I know I've seen this material before, but it's been so long, I'd completely forgotten how to do it. I don't even know how to get started.

My TEAs test was suppose to be last Saturday...but being how sick I was, I had to reschedule it for this upcoming Saturday instead. My scores in progressive practice assessments are getting better, but the science portion is really messing me up. Especially ones involving chemical reactions such as this one.

Please help...any constructive input would help me out a lot. Thank you so very much.

[emcadams]

Well, you may find some help if you still have your Chemistry book, or just looking at a Chemistry for dummies book at the library.

This looks like a single replacement reaction...so Ca would replace the H2. Since SO4 has a -2 charge, Calcium would have to oxidize (lose electrons), to bond with the SO4. To work this problem, you first need to know what the end product would be. That would be H2 (hydrogen gas) and CaSO4 (calcium sulfate). Hydrogen sulfide is H2S, so that doesn't even exist in this problem. Remember from your chemistry that SO4 is a polyatomic ion with a 2- charge, so it is not going to break down in the reaction.

Through my TEAS studying (and test) seem to focus on balancing single and double replacement reactions. So I would take a look at a chem chapter and study up on that. Then I would take a look at redox (reduction/oxidation) reactions. Reducing means gaining elections, oxidizing means losing electrons. No simple answer, unfortunately...they are testing your retention of your chemistry material.