What is the concentration of a dextrose solution prepared by diluting 19 ml of a 4.0 m dextrose solution to 25 ml using a 25 ml volumetric flask?

3.04 M

Explanation:

Dilution is the process of decreasing the concentration of a solute in a solution, usually simply by mixing with more solvent like adding more water to a solution. To dilute a solution means to add more solvent without the addition of more solute.

When a solution of given molarity  and volume is diluted its new concentration can be found using the formulae :

in the given problem

so upon substituting thse values in the above equation we get our resulting concentration to be 3.04 M

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.