What is the basicity of phosphoric acid?
a number of measure of proton reacting with a base
What is 0.40 moles of phosphoric acid?
Phosphoric acid has the formula H3PO4 so if you add up these numbers from the periodic table you find the Molar mass of phosphoric acid is 98 (1+1+1+31+16+16+16+16). this is the mass (in grams) of one mol of phosphoric acid (or 6.02 x 10^23 atoms of phosphoric acid) So times this number by 0.4 to find the mass of 0.4mol of phosphoric acid=39.2 grams