| − | A '''critical mass''' is the amount of a radioactive [[isotopes|isotope]] necessary to cause an explosion due to a chain reaction.<ref>Wile, Dr. Jay L. ''Exploring Creation With Physical Science''. Apologia Educational Ministries, Inc. 1999, 2000</ref>
| + | The term "'''critical mass'''" refers to the amount of a radioactive [[isotopes|isotope]] necessary to cause an explosion due to a chain reaction.<ref>Wile, Dr. Jay L. ''Exploring Creation With Physical Science''. Apologia Educational Ministries, Inc. 1999, 2000</ref> |