Question

what is one of the requirements for a chemical reaction to occur according to collision theory? sufficient energy and proper orientation of particles. low energy and random orientation of particles. high temperature and pressure. presence of a catalyst.

Explanation:

According to collision theory, for a chemical reaction to occur, particles must collide with sufficient energy (activation energy) to break bonds and with the proper orientation so that new bonds can form. Low energy won't break bonds, random orientation may not allow effective bond - forming. High temperature and pressure are not fundamental requirements of the theory itself (though they can affect energy and collision frequency). The presence of a catalyst is not a requirement for a reaction to occur (a reaction can occur without a catalyst, just slower in some cases), it just speeds up the reaction.

Answer:

Sufficient energy and proper orientation of particles.