What does the concentration of a solution refer to? in what 3 ways can concentration be expressed?

The concentration of a solution refers to its macroscopic property, represents the amount of solute dissolved in a unit amount of solvent or of the solution, and can be expressed in a variety of ways such as qualitatively (dilute, concentrated) and quantitatively ( saturated, unsaturated.)

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.

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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.  

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