This statement would be best characterized by the law of conservation of momentum—choice C.
All atoms of the same element have the same atomic number
Here are the list of nucleo bases : adenine , Thymine, Guanine , Cytosine
Adenine pairs with Thymine, and Guanine pairs with Cytosine
Adenine + Guanine = Purine
Thymine + Cytosine = Pyrimidine
So the answer for number 1 will be : Purine, since Adenine is not the choice
And the answer for number 2 is Guanine
hope this helps
(a) sodium hydroxide + ammonium sulfate --> sodium sulfate + ammonium hydroxide
sodium sulfate precipitates in aqueous solutions
(b)<span> niobium(V) sulfate + barium nitrate → Barium sulfate + niobium nitride
both do not precipitate in aqueous solution
</span>(c) strontium bromide + silver nitrate ---> strontium nitrate + silver bromide
both do not precipitate in aqueous solution
This is a combination reaction. Look at the 2 elements on left and a compound on the right.