Why is it so many numbers

Flourine is found to undergo 10% radioactivity decay in 366 minutes determine its halflife

How many molecules are found in 1.32 mol of nacl?

What volume of a 0.0606 m solution of strontium bromide is needed to obtain 0.340 mol of the compound? question 42 options: a)5.61 l b) 3.4 l c) 600 ml d) 1 l e) 178 ml