I will take a stab at it, but there are not equations, did you forget them?
Answer:
1.20 M
Explanation:
Convert grams of Na₂CO₃ to moles. (50.84 g)/(105.99 g/mol) = 0.4797 mol
Molarity is (moles of solute)/(liters of solvent) = (0.4797 mol)/(0.400 L) = 1.20 M
the molar mass is how many grams it takes to make a full mole. The number in carbon 12 tells us that it takes 12 g to makes a mole, so one half of that would be <u><em>option d, 0.5</em></u>.
A weak bond between two molecules resulting from an electrostatic attraction between a proton in one molecule and an electronegative atom in another