Revision: Radioactivity Report a question What's wrong with this question? You cannot submit an empty report. Please add some details. 21 Radioactivity - Revision Quiz Test your understanding of Radioactivity here: 1 / 5 1) Radioactive decay is said to be spontaneous. What is meant by spontaneous? A process where an unstable atomic nucleus emits radiation without any external influence. A process where an unstable atomic nucleus emits radiation in an undetermined direction. A process where an unstable atomic nucleus splits into two or more fragments. A process where two unstable atomic nuclei join to form one large nucleus. 2 / 5 2) The charge on an alpha particle is how many times that of the charge on a proton? one times two times four times three times 3 / 5 3) The mass of an alpha particle is how many times that of the mass of a proton? three times one times two times four times 4 / 5 4) The table shows the results of an experiment to find the half-life of a radioactive substance. What is the half-life of the substance? 120 s 240 s 60 s 180 s 5 / 5 5) A powder contains 400 mg of a radioactive material that emits α-particles. The half-life of the material is 5 days. What mass of that material remains after 10 days? 200 mg 0 mg 40 mg 100 mg Your score is Restart quiz
