A solution contains 35 grams of KNO3 dissolved in 100 grams of water at 40°C. How much more KNO3 would have to be added to make it a saturated solution?

32g

Explanation:

potassium nitrate has solubility of about 67g per 100g of water at 40°C, which means that potassium nitrate solution will contain 67g of dissolved salt for every 100g of water.

since at this temperature, our solution contains  35g of potassium nitrate 100g  of water. The solution will be unsaturated because of the less potassium nitrate.

to make saturated solution,

mass of potassuim nitrate = 67g - 35g

= 32g

which means dissolving another  32g  of potassium nitrate in solution at 40 °C will make saturated solution.

the law of conservation of mass states that in a chemical reaction, the total mass of reactants is equal to the total mass of products. because atoms are only rearranged in a chemical reaction, there must be the same number of sodium atoms and chlorine atoms in both the reactants and products

what is the question?