Muriatic acid, sold for adjusting the pH of swimming pools and for cleaning freshly poured concrete, is a concentrated solution of hydrochloric acicd in water. Its density is 1.18 gm/ml, and is typically 36.5% HCI by mass. How many grams of HCI are in a quart of muriatic acid?

What grade are you in? This should be very easy. Find a conversion table and see how many milliliters are in a quart. Then, given that you know how many grams per ml, it's simple arithmetic.