I'm not sure, but maybe burning point...
Answer:
Biphenyl
Explanation:
The reaction of bromo benzene with magnesium-ether solution yields a Grignard reagent.
The byproduct of this reaction is biphenyl. It is formed when two unreacted bromobenzene molecules are coupled together.
Hence, It is advised that the bromobenzene solution be added slowly to the magnesium-ether solution so that it isn't present in a high concentration, thus reducing the amount of biphenyl by-product formed.
276 grams of carbon in 23.0 moles
<u>Answer:</u> The equation is given below.
<u>Explanation:</u>
Single replacement reactions are the chemical reactions in which more reactive metal displaces a less reactive metal from its chemical reaction. General equation for these reactions is given by the equation:

Metal A is more reactive than metal B.
The reactivity of metals is judged with the help of reactivity series. In this series, the metals lying above are more reactive than the metals which lie below in the series.
For the reaction of solid lithium metal and nitric acid, the equation follows:

This is a type of single replacement reaction because Lithium (more reactive metal) is replacing Hydrogen (less reactive metal) from the chemical reaction.
Answer:
5 000 000 (5 million atoms)
Explanation:
Let us assume that a vanadium atom has a spherical shape.
diameter of a sphere = 2 x radius of the sphere
Thus,
Radius of a vanadium atom = 130 pm
= 130 x
m
The diameter of a vanadium atom = 2 x radius
= 2 x 130 x
= 260 x
m
Given a distance of 1.30 mm = 1.30 x
m,
The number of vanadium atoms required to span the distance = 
= 5000000
Therefore, the number of vanadium atom that would span a distance of 1.30 mm is 5 million.