To make NaTcO4, Tc metal is dissolved in nitric acid to make HTcO4, NO2 and H2O. Then the product HTcO4 is treated with NaOH to make NaTcO4. If you begin with 4.5 mg of Tc metal, how much of NaOH (in grams) is required to convert all of the HTcO4 into NaTcO4?

Question

I don't even know what equation to use or where to start. There doesnt seem to be enough information given in the problem. Plz help me if you can!

Thanks!

Answer 1

There is more than enough information in the question.

First start with the two equations.

Tc + HNO3 = HTcO4 + NO2 + H2O (needs to be balanced)

HTcO4 + NaOH = NaTcO4 + H2O (this is balanced)

from the second equation we see that 1 mole of NaOH reacts with 1 mole of HTcO4. So if we find the number of moles of HTcO4 produced this is also the number of moles NaOH needed.

Once you have balanced the first equation you can calculate the number of moles of Tc metal used, hence the number of moles of HTcO4 produced.

Hope this helps.