Asalt is best described as a compound that is formed from the reaction between
an acid and a base.
a strong acid and a weak acid.
a strong base and a weak base.
an acid and water.

A salt is best described as a compound that is formed from the reaction between a strong acid and a strong base. It is sometimes called a neutralization reaction. An example is the reaction between hydrochloric acid and sodium hydroxide. It will form water and sodium chloride (a salt).

The right answer is A (strong acid with strong base).

The reaction of an acid with a base to produce salt and water alone is called a neutralization reaction.

A salt is a compound formed following a replacement of the hydrogen ions (H +) of an acid with a basic radical during a reaction.

A normal salt is formed by the complete replacement of the H + of an acid (example Na2CO3).

while an acidic salt is formed by the incomplete replacement of the H + of an acid (eg NaHCO3).

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.  

6.4 cm (max) - 25 cm (min)