A nucleotide is composed of a phosphate group, sugar, and nitrogen base. DNA is made of 2 strands of nucleotides linked together by covalent bonds between the phosphate and sugar of each nucleotide. The strands of nucleotides are linked together by hydrogen bonds creating DNA. Hope this helps and sorry if I made a mistake.
Well you have to mix chemicals which caused a chemical reaction. When you mix salt and ice the freezing point of liquid changes. the ice gets colder
The first one because some people might not believe that and others might believe that.
Answer/Explanation:
In June 1998 in Japan a scientist discovered that neutrinos (which is a type of particle) has weight, mass. This was later proven with some very convincing strong evidence.
<u><em>~ LadyBrain</em></u>
Explanation:
Since, the atomic number of nitrogen is 7 and its electronic distribution is 2, 5. So, in order to attain stability it needs to gain 3 electrons.
Hence, when it chemically combines another nitrogen atom then as both the atoms are non-metals. So, sharing of electrons will take place.
Also, there is no difference in electronegativity of two nitrogen atoms. Hence, compound formed 
is non-polar covalent in nature.
