Answer:
to become a noble gas element P will have 2 electrons in it's outer most energy level if it has one energy level
and eight in the last energy level if more than one
(1) 36 days is 8 half-life periods,
so 24mg becomes 24mg times (1/2)^8 = 24 mg/256 = 0.094 mg
(2) 9.6/1.2 = 8, which means three half-life periods went by.
At the end of 4.5 days, there were 4.8 mg
At the end of 9.0 days, there were 2.4 mg
At the end of 13.5 days, there were 1.2 mg
(3) The activity is proportional to the amount of radioactive material remaining,
so after two half-life periods, the activity should be 1/4 of what it originally was.
So the initial activity was probably 12.0 Ci
Option c is correct bcoz neutrons and protons exist inside nucleus whereas electrons revolve around it
hope it helped
Catalysts are substances that speed up the rate of a chemical
reaction. It is important to know that reacting species must first possess a
minimum amount of energy equal to the activation energy for the reaction
to proceed. The catalyst works in a way that lowers the activation energy
required for the reaction to proceed. In this way, the reaction occurs at a
faster rate than without a catalyst. Catalysts do not react with
the chemical species in the reaction, thus, they are not consumed. However, over
time, catalysts tend to degrade and their function is also reduced. When this
happens, new catalysts replace the poisoned ones. Catalysts are widely used
today since they bring an increase in the production rate of commercial chemicals.