How can you find the energy levels of an atom

What is the mass of sodium in 3 moles of sodium chloride

Match the name of the following compound:   mgso4  · h2omagnesium sulfate monohydratemagnesium (ii) sulfate monohydratemagnesium (ii) sulfate hydratemagnesium sulfate hydrate

The reactions shown here can be combined to make the overall reaction c(s) + h2o(g) ⇌ co(g) + h2(g) by reversing some and/or dividing all the coefficients by a number. a. c(s) + o2(g) → co2(g) k=1.363×10^69 b. 2 h2(g) + o2(g) → 2 h2o(g) k=1.389×10^80 c. 2co(g) + o2 (g) → 2 co2(g) k=1.477×10^90