H2 <span>because the smaller the gas molecule, the faster the diffusion. (the lightest molecule will diffuse the quickest)</span>
Answer:- 23.0 mg
Solution:- Radioactive decay obeys first order kinetics and the first order kinetics equation is:
where, 
is the initial amount of radioactive substance and N is it's amount after time t. k is the decay constant.
From given information, Original amount, of the radioactive substance is 184 mg and we are asked to calculate the amount N after 15 days. It means, t = 15 days
Half life is given as 5 days. From the half life, we could calculate the decay constant k using the equation:
where, 
is the symbol for half life. let's plug in the value of half like to calculate k:
Let's plug in the values in the first order kinetics equation and solve it for N:
lnN = 3.136
N = 23.0 mg
So, 23.0 mg of Bi-210 would be remaining after 15 days.
Answer:
How many atoms of each element are there in one molecule of H3PO4? there are 8 atoms in total in H3PO4. there are 3 atoms of hydrogen, 1 atom of phosphorous and 4 atoms of oxygen in the one molecule of this compound, which is called hydrogen phosphate.
Metals are on the left side of the table and nonmetals are on the left with metalloids between them. And the noble gases are all in group 18 of the periodic table.
