Answer;
= 5 M or 5 moles/liter
Explanation;
At point E, 90 g of substances X are dissolved in 100 g of the solvent.
100g of the solvent is equal to 100 ml
Molarity is the number of moles of a substance in one liter of a solvent.
90 g of X are in 100 ml
But; the RFM of X = 180 g/l
Therefore; the moles of X in 90 g = 90/180
= 0.5 moles
Therefore;
0.5 moles of X are contained in 100 ml of the solvent;
Thus, molarity = 0.5 × 1000/100
= 5 M or 5 moles/liter
