Explanation:
An oxidation number is a number that is assigned to an atom in a substance. The oxidation number could be positive, negative, or zero, and it indicates if electrons are lost or gained. In other words, the oxidation number is a number that helps us keep track of electrons in an atom.
Answer:
-4
Explanation:
In 0.0034 the zeros are preceding numberd and after the decimal point.
Baking something(chemical) and a ice crem melting (phyisical)
Answer:
Chemicals are used in the manufacturing of fertilizers
Answer: 3.306 mmol
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per Liter of the solution.

where,
Molarity
n= moles of solute
= volume of solution in ml

According to stoichiometry:
1 mole of
gives 2 moles of 
1.653 mmol of
gives =
of 
Thus number of millimoles of
are 3.306