Comments on: O Level Chemistry – Atomic Structure

By: sean

sean — Wed, 05 May 2010 15:45:34 +0000

Well Done!

Keep Learning! =)

By: SimpleChemConcepts | O Level Chemistry - Isotopes

SimpleChemConcepts | O Level Chemistry - Isotopes — Wed, 24 Feb 2010 16:14:56 +0000

[...] we have discussed on the atomic number (Z) and atomic mass (A) that are related to a chemical [...]

By: Danyyal Ahmed

Danyyal Ahmed — Sat, 06 Jun 2009 16:10:54 +0000

Question 1:
Which one of the following statements is correct?
Carbon has atomic number 6 and mass number 12. This means that in the nucleus of this atom there are:
a) 12 protons and no neutrons
b) 2 protons for every neutrons
c) 2 neutrons for every proton
d) Equal number of protons and neutrons

Question 2:
Deduce the number of protons, neutrons and electrons in an atom of Antimony-122.

Question 3:
In the Periodic Table, the elements are arranged in order of
a) atomic number
b) mass number
c) number of neutrons
d) number of isotopes

ANSWERS:

D) equal number of protons and neutrons

2) protons: 51
electrons:51
neutrons: 71

3) atomic number

By: sean

sean — Mon, 01 Jun 2009 17:07:12 +0000

Hi Nazneen,

From the Periodic Table, you will find out the Antimony has Atomic Mass Number (A) to be 122 and an Atomic Number (Z) to be 51.

From those information, you can find the answers to be:

No. of Protons = Atomic Number = 51

No. of Electrons = No. of Protons = 51

No. of Neutrons = Atomic Mass Number – No. of Protons = 122 – 51 = 71
(since Atomic Mass Number = No. of Protons + No. of Neutrons)

Hope this explanations helps.

Let me know if you more clarification.

PS: Do check out other questions in this blog and participate to learn.

Cheers,
Sean
Master Trainer @ SimpleChemConcepts.com
Author of UP YOUR CHEMISTRY GRADES NOW! book

By: nazneen

nazneen — Sun, 17 May 2009 15:50:15 +0000

how did u get the answer for number 2??