A student measures the mass of a metal sample as 12.450 g and its volume as 4.50 mL. What is the density of the metal, reported to the correct number of significant figures?

A water sample contains 5 mg of dissolved chloride ions per liter of solution. This concentration is equivalent to:

Which type of radioactive emission has NO mass and NO charge, consisting of high-energy electromagnetic radiation?

What is the molarity of a solution that contains 0.500 mol of NaCl dissolved in enough water to make 250 mL of solution?

The reaction 2 H₂(g) + O₂(g) → 2 H₂O(l) is best classified as which type of reaction?