Option c
water is non polar and can dissolve non polar compounds such as oil
water is unable to dissolve or mix with substances like oil therefore making the statement false
Ionic bonds are formed due to tendency of a metal to donate an electron and tendency of non metal to gain an electron.
Ln(800/3200) = - kt
t = 24 years.
ln(0.25) = -k*24
(- 1.3863) = -k*24
1.3863 / 24 = k
0.05776 = k
ln(0.5) = -k*t
-0.6931 = - 0.05776 t
12 = t
I don't know if you can just look at the question and know the answer. If 24 years is a quarter life then is it obvious that the 1/2 life is 12 years? It might be, but the method I've used works for sure.