He, because it’s a noble gas which they have full valence electrons (occupied energy levels)
Answer:
10 neutron
Explanation:
No.of neutron=Mass no. -- atm no.(or no.of p)
No of neutron=19 -- 9
=10
Answer:
For example, when we bake a cake, it's a result of a mixture of eggs, flour, sugar, and other ingredients. Any time two or more items are combined, a mixture is formed. Sometimes, the different parts of a mixture can be separated into individual entities. Other times, they're married for as long as they exist.
Explanation:
Answer:

Explanation:
Given that:
Half life =
days
Where, k is rate constant
So,
The rate constant, k = 0.00007 days⁻¹
Using integrated rate law for first order kinetics as:
Where,
is the concentration at time t
is the initial concentration
Given:
5 % is lost which means that 0.05 of
is decomposed. So,
= 1 - 0.05 = 0.95
t = ?
t = 732.76 days = 
There are two oxygens on the left side of the equation and three on the right