What is the concentration of sodium ions in a (2.2x10^0) mol/L solution of sodium carbonate? (answer to 2 s.d. in mol/L}

1 Answer
May 29, 2017

Answer:

#4.4 * 10^0"mol L"^(-1)#

Explanation:

Sodium carbonate, #"Na"_color(red)(2)"CO"_3#, is an ionic compound that, as its name and chemical formula suggest, contains sodium cations and carbonate anions in a #color(red)(2):1# ratio.

This salt is soluble in water, which means that every time #1# mole of sodium carbonate dissolves in water, it produces #color(red)(2)# moles of sodium cations and #1# mole of carbonate anions in aqueous solution.

#"Na"_ color(red)(2)"CO"_ (3(aq)) -> color(red)(2)"Na"_ ((aq))^(+) + "CO"_ (3(aq))^(2-)#

This tells you that a sodium carbonate solution will always have

#["Na"^(+)] = color(red)(2) * ["Na"_ 2"CO"_3]#

In your case, the solution will have

#["Na"^(+)] = color(red)(2) * 2.2 * 10^(0)# #"mol L"^(-1)#

#color(darkgreen)(ul(color(black)(["Na"^(+)] =4.4 * 10^0color(white)(.)"mol L"^(-1))))#

The answer is rounded to two sig figs.