The atomic number or (also called) the proton number, represents the number of protons, which also represents the number of electrons in that single atom itself (an atom which has not gone through reactions of any kind will have the same number of electrons as number of protons).
Hope this helps! :)
P.s. This question seems more of a Chemistry than Biology question in my opinion
Adenine which is a purine base, always pairs with the pyrimidine Thymine in DNA and Uracil(also a pyrimidine) in RNA. The bond which is present between the two bases is a double hydrogen bond.
Guanine which is also a purine base, always pairs with the pyrimidine Cytosine, in the case of both, DNA and RNA. The bond which is present between the two bases is a triple hydrogen bond and hence, is stronger than the A-G double bond.
63 in water 100/g KNO3 Potassium nitrate
ADP (adenosine diphosphate)
