Question

An element X has mass number 35 and number of neutron is 18.Identify the group number and period of element X

Answer 1

Hey


Given that :-

♦ Atomic mass = 35

♦ Number of netrons = 17

We know that ,

Number of neutrons + number of protons = atomic mass

So ,

Number of protons + 18 = 35

=> Number of protons = 35 - 18

=> Number of protons = 17 .

Now ,

Number of electrons = number of protons

So ,

Number of electrons = 17 .

So this element X is Chlorine .

Chlorine has atomic number 17 .

It's valency is 1 . So it is in 17th group .


thanks :)

Answer 2

Heya,

According to the question,

Mass of element X = 35
No. of neutron = 18

So,
No. of protons = Mass of element - No. of neutron
= 35 - 18
= 17

No. of protons = No. of electron
Therefore,
No. of electron = 17

So,
Atomic Number = 17

Therefore,
Element X is 'Clorine(Cl)'

Period of Cl = 3rd period

Group of Cl = 17th group

Hope this helps.....:)