Before you begin titration, drops of indicator are added to the Erlenmeyer flask. This happens when preparing to measure pH change.
<u>Answer:</u> The net ionic equation is written below.
<u>Explanation:</u>
Net ionic equation of any reaction does not include any spectator ions.
Spectator ions are defined as the ions which do not get involved in the chemical equation. It is also defined as the ions which are found on both the sides of the chemical reaction when it is present in ionic form.
The chemical equation for the reaction of copper (II) chloride and potassium phosphate is given as:

Ionic form of the above equation follows:

As, potassium and chloride ions are present on both the sides of the reaction, thus, they will not be present in the net ionic equation.
The net ionic equation for the above reaction follows:

Hence, the net ionic equation is given above.
Answer:
D. the total mass that element contribute to a molecule
CH3 would methyl group, CH2 would be Methylene C is Carbo, and Ch is <span>Methylidyne</span>