What is the number of nitrogen atoms in 12.0 g of
CO(NH2)?
[Avogadro constant = 6.02
x 1023 moll; Molar mass of
CO(NH2) = 60 g mol']

1.2 x 10²³atoms

Explanation:

Given parameters:

Mass of CO(NH₂)  = 12g

Unknown:

Number of Nitrogen atoms = ?

Solution:

Given compound;

     CO(NH₂);

  In;

         1 mole of CO(NH₂), we have 1 mole of N

let us find the number of moles of CO(NH₂);

  Number of moles  =

  Number of moles  =   = 0.2moles

Since

                  1 mole of CO(NH₂), we have 1 mole of N

                0.2 mole of CO(NH₂) will have 0.2mole of N

            1 mole of a substance contains 6.02 x 10²³ atoms

           0.2 mole of N will contain 0.2 x 6.02 x 10²³ atoms = 1.2 x 10²³atoms

the answer would be c

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.