Mole concept

Calculate the number of iodine atoms in 4.50g of iodine gas

0.017g/mol

Explanation:

according to the mole concept to calculate the number of moles of a substance you use the formula

number of moles= mass/molecular mass

=4.5g/254g/mole

=0.017moles

I hope this helps and sorry if it's wrong

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.  

gold is my favorite solid.