need to know the equation for solving my problem

Question

An Aton of Chlorine (CL) has 6 more protons than an atom of sodium (NA). The atomic number of chlorine is 5 less than twice the atomic number of sodium. The atomic number of an element is equal to the number of protons per atom.

a. How many protons are in an atom of chlorine

b. What is the atomic number of sodium

Answer 1

Z = atomic number

 

(i)   Z_Cl = Z_Na + 6

(ii)  Z_Cl = 2Z_Na - 5

 

(ii) - (i) ⇒ 0 = Z_Na - 11

 

Z_Na = 11

Z_Cl = Z_Na + 6 = 11 + 6 = 17