Answer: The half-reactions represents reduction are as follows.
Explanation:
A half-reaction where addition of electrons take place or a reaction where decrease in oxidation state of an element takes place is called reduction-half reaction.
For example, the oxidation state of Cr in
is +6 which is getting converted into +3, that is, decrease in oxidation state is taking place as follows.

Similarly, oxidation state of Mn in
is +7 which is getting converted into +2, that is, decrease in oxidation state is taking place as follows.

Thus, we can conclude that half-reactions represents reduction are as follows.
Dihydrogen oxide is the right answer. Dihydrogen oxide is just 2 hydrogen and 1 oxygen which is H2O or water.
Within the options, we have four organic compounds. Let's see what the skeletal structure of the compounds is in order to identify them better:
The first compound CH3OCH3 has two methyl groups linked by a carbon atom, this type of compound is called an Ether
The second compound has a double bond, it is badly written but it seems that is an alkene.
The third compound has two methyl groups linked by nitrogen atoms, therefore will be an amine.
The last compound has a hydroxyl group, therefore it is an alcohol
Answer:
CH3OCH3 Ether
CH2CH2CHCH2CH3 Alkene
CH3NHCH3 Amine
CH3CH(OH)CH₂CH3 Alcohol
Answer:
The correct options are;
C. The magnitude of attraction from its nucleus
D. The distance between the electrons and its nucleus
Explanation:
The atomic radius reduces, within a given period, as we move from left to right, the number of protons increases alongside the number of electrons and the while the quantum shell to which the extra electrons are added to is the same. Therefore, the radius of the atom is dependent on the magnitude of the attraction from the nucleus
Similarly, as we progress to the next period, with an extra quantum shell, the atomic radius is seen to increase.
Therefore, the atomic radius is determined by the distance between the electrons and its nucleus.