Isotopes & Isotopic Abundance

(Photo Credit x-ray delta one)

One of the very important concepts in Chemistry is Isotopes which is defined as “Atoms of the same element with different numbers of neutrons but same number of protons”.

For example, Hydrogen itself has 3 isotopes, each differing in the number of neutrons.

It is importent to know the similarity and differences of Isotopes of An Element. Let’s take a look:

Similarity:

• Same proton number
• Same number of electrons in a neutral atom
• Same electronic configurations
• Same chemical properties

Differences:

• Different numbers of neutrons in an atom
• Different nucleon or mass number
• Different relative isotopic mass
• Different physical properties such as melting point, density, etc

Let’s try out a question on Isotopes.

Question:

A sample of hydrogen consists of the isotopes ¹H, ²H and ³H. A sample of oxygen only contains ¹⁶O.

i) Write the formulae of all the different water molecules that can be formed from these samples. How many different types can you find?

ii) Which molecule has the largest mass?

PS: Try it out and leave the answer in the comments section below. I would love to hear from you.

Stay tuned for the next post – i will share with you more on Calculations involving Isotopic Abundance.

Related Articles:

• Calculating Relative Atomic Mass from Isotopic Abundance
• Sub-Atomic Particles of Atoms
• Calculation of Ar based on Isotopic Abundance
• Calculation of Ar based on Isotopic Abundance – Challenging Question
• Common Errors in Calculating Empirical Formula