What is the mass of 0.5 moles of carbon tetrafluoride, CF4?

44.0015

Explanation:

we go and look at the mass for carbon which is 12.011 then at the mass of fluorine which is 18.998. Since there are 4 Fluorines the we multiply 4 by 18.998 which we get 75.992. Then we add 75.992 + 12.011 which will give us 88.003 then multiply 88.003 by 0.5 which gives us 44.0015

Different radioactive nuclides decay into their respective daughter nuclides at distinct rates. Some of the nuclides decay briskly, while others decay gradually. The time it consumes for half of the parent nuclide in a radioactive sample to decay to the daughter nuclides is known as the half-life of the radioactive sample.  

The nuclides, which decay briskly exhibit short half-lives and are very active. The half-life can be utilized to find the rates of radioactive decay. In the given question, the half-lives of various nuclides are given. So, the order to the most active (shortest half-life or largest number of decays per second) to least reactive (largest half-life or the smallest number of decays per second) is:  

Tc-99m > Y-90 > In-111 > I-131