Does This Reaction Happen

Multiple-choice exercise

For each of these reactions, decide if the reaction actually occurs. You will need an activity series for the single replacement reactions, and a solubility table for the double replacement reactions.

Predictions Involving Single and Double Replacement Reactions

Single replacement reactions occur if the lone element can replace a similar element in a compound. Metals can replace less active metals. Some metals can replace hydrogen in acids. Very active metals, such as sodium and potassium, can replace hydrogen in water. Halogens can replace other halogens. An activity series of the elements is used to make definitive decisions about the validity of single replacement reactions.

Double replacement reactions happen if they produce any of these three substances:

  • Water
  • Gas
  • A precipitate

The formation of a precipitate is predicted with a solubility table. Substances that are insoluble or partially soluble precipitate. Soluble substances do not precipitate.