Assertion: actinium's number | /r/Synonym | the mass defect
Facets:
Source sentences:
text: There are two reasons for the difference between mass number and isotopic mass, known as the mass defect:
text: There are two reasons for the difference between mass number and isotopic mass, known as the mass defect:
text: There are two reasons for the difference between mass number and isotopic mass, known as the mass defect: