<span>Salt is the product formed by a reaction in which the hydrogen atoms of an acid are replaced by the atoms of a metal. The salt is formed as a result of the neutralization of the acid by base, that is the metal or positive ion replace the hydrogen ion in the acid. For instance: NaO + H2SO4 = NaSO4 + H2O. In this example, Na [sodium] has replaced the hydrogen in H2SO4, thereby forming the salt NaSO4.</span>
The best answer to your question would be B:those who could not be broken down by physical means.
Explanation:
A chemical reaction is one in which a chemical change occurs.
During a chemical change;
- The process is irreversible
- New kinds of matter produced
- There is a change in mass
Based on these premise;
Baking cake batter is a chemical reaction because you cannot reverse the process
Shredding a paper is not a chemical reaction because no new kind of matter is produced.
Twisting of a metal wire is not a chemical reaction
Yellowing of newspaper in sunlight is a chemical change. The process cannot be reversed
Answer:

Explanation:
Given that,
The mass of the rock, m = 15 g
The volume of the rock, V = 10 cm³
We need to find the density of the rock. The density of an object is equal to the mass per unit volume such that,

So, the density of the rock is equal to
.