How many formula units are in 0.25 mole of NaCl?

The meaning and usefulness of the mole Page 2 2 • One mole of NaCl contains 6.022 x 1023 NaCl formula units. Use the mole quantity to count formulas by weighing them. The mass of an atom in amu is numerically the same as the mass of one mole of atoms of the element in grams.

Explanation:

Formula Units = mole x Avogadro's Number

Formula Units of NaCl = mole NaCl x Avogadro's Number

Formula Units of NaCl = 0,25 mole x 6,022 x 10²³ molecule

Formula Units of NaCl = 1,5055 x 10²³ molecule

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.  

b.

the accuracy of the data.