Answer:
3,5-dimethyl-2-octene
Explanation:
The parent chain will be choosen based on the highest value. In this case, if we count from top to bottom, we'll get seven carbon, however if we count from the second carbon, going left and then down, we'll get eight carbon. So the parent chain is octene
The double bond is located at the second carbon and the methyl groups are located on carbon 3 & 5. Since there are two methyl groups, we add di- in front of methyl to indicate two methyl groups present.
Note: The functional group has to be prioritise and it needed to be a part of the parent chain. In this case, the functional group is the double bond. (alkene)
Aluminum atomic number 13 becomes Neon with an atomic number of 10 when it loses three valence electrons.
Answer:

Explanation:
Given:
A solution contains one or more of the following ions such as Ag,
and 
Here the Lithium bromide is added to the solution and no precipitate forms
Solution:
Since with LiBr no precipitation takes place therefore Ag+ is absent
Here on adding
to it precipitation takes place.
Precipitate is as follows,

Thus,
is present
When
is added again precipitation takes place.
Therefore the reaction is as follows,

Therefore,
are present in the solution
Explanation:
Groups are numbered 1–18 from left to right. The elements in group 1 are known as the alkali metals; those in group 2 are the alkaline earth metals; those in 15 are the pnictogens; those in 16 are the chalcogens; those in 17 are the halogens; and those in 18 are the noble gases.