The hardness of water (hardness count )is usually expressed in parts per million(by mass) caco3, which is equivalent to milligrams of caco3 per litre of water. what is the molar concentration of ca2+ ions in a water sample with a hardness count of 175 mg caco3/l?

Apure solvent has a vapor pressure the vapor pressure of a solution. a. equal to b. lower than c. higher than

How many grams of co(g) are there in 74.5 ml of the gas at 0.933 atm and 30o c?

Modern pennies are composed of zinc coated with copper. a student determines the mass of a penny to be 2.482 g and then makes several scratches in the copper coaling (to expose the underlying zinc). the student puts the scratched penny in hydrochloric acid, where the following reaction occurs between the zinc and the hcl (the copper remains undissolved): zn(s) + 2 hcl(aq) → h2(g) + zncl(aq)the student collects the hydrogen produced over water at 25 °c. the collected gas occupies a volume of 0.899 l at a total pressure of 79 j mmhg. calculate the percent zinc (by mass) in the penny. (assume that all the zn in the penny dissolves.)