1) Acidic solution. An acidic solution has a high concentration of H+ ions.
2) Basic solution. A basic solution has a high concentration of OH- ions.
3) HCl chemical reaction.

You can also write it as follows

4) pH scale.
When the concentration of H+ is high, the solution is acidic. H+ lowers the pH of the solution.
Option D.
Answer:
1.6 g/cm3
Explanation:
The formula for Density is actually D=m/v
m= 12.9g
v= 8 cm3

The unit is grams per centimeters cubed or g/cm3
(If you use the formula given in the question it would be D=0.62)
The right answer is physical change.
In the general sense, dissolution is the action of dissolving something, that is to say, of decomposing it by the separation of its parts.
In chemistry, dissolution is an intimate mixture of two bodies, at least one of which is liquid.
Eg: the dissolution of sugar in the water, the sugar will pass from the solid and dry state to the dissolved state so there is a physical change. The sugar is going to be surrounded by water molecules and form hydrogen bonds, so it can be a chemical change.
Fossil fuel will eventually generate co2 in to air and ot will lead to green haouse effect