<u>Answer:</u> The correct answer is Option C.
<u>Explanation:</u>
Net ionic equation of any reaction does not include any spectator ions.
Spectator ions are defined as the ions which does not get involved in a chemical equation. They are found on both the sides of the chemical reaction when it is present in ionic form.
The chemical equation for the reaction of sodium bicarbonate and acetic acid is given as:

Ionic form of the above equation follows:

As, sodium and acetate ions are present on both the sides of the reaction. Thus, it will not be present in the net ionic equation and are spectator ions.
The net ionic equation for the above reaction follows:

Hence, the correct answer is Option C.
The theory of evolution was proposed by Darwin.
Answer: (C) Vaporizing
Explanation:
Vaporization is the process in which the substance change the state of of liquid into the gas state.
The vaporization process require the largest input of the energy as when the state is in the solid state then, the solid substances contain the strong forces of the attraction and they require high energy to break these strong bonds.
For changing the liquid state into the gases state we require to overcome the surface tension and require enough energy for acquiring the vaporization state.
Therefore, option (C) is correct.
Answer:
The area of the given rectangular index card = <u>9677.4 mm²</u>
Explanation:
Area is defined as the space occupied by a two dimensional shape or object. The SI unit of area is square metre (m²).
<u>The area of a rectangle</u> (A) = length (l) × width (w)
Given dimensions of the rectangle: Length (l) = 5.0 inch, Width (w) = 3.0 inch
Since, 1 inch = 25.4 millimetres (mm)
Therefore, l = 5 × 25.4 = 127 mm, and w = 3 × 25.4 = 76.2 mm
Therefore, <u>the area of the given rectangular index card</u> = A= l × w = 127 mm × 76.2 mm = <u>9677.4 mm²</u>
Answer:
1.2 g/ ml
Explanation:
The volume of the mineral = increase in volume of the water whuich is 16 - 8 = 8mls.
Therefore the mineral's density = 9.6 / 8
= 1.2 g/ ml answer