Question

The Kohinoor diamond was the largest diamond ever found. How many moles of carbon atoms are present in it, if it weighs $ 3300 $ carats? [Given: $ 1 $ carat $ = 200{\text{mg}} $ ]

Answer 1

Hint: This is a very easy question which can be solved by doing a simple conversion. To solve this question, we have to convert carats into milligram or later in grams. And then we will use simple application of the mole concept.

Complete Step-by-Step Solution
It is provided in the question that
 $ 1 $ carat $ = 200{\text{mg}} $
And it is stated in the question that the Kohinoor diamond weighs $ 3300 $ carats.
So, the weight of $ 3300 $ carats will be equal to
 $ 3300 \times 200 = 660000{\text{mg}} $
Now, we need to convert this milligrams value into grams
We know that $ 1000{\text{mg}} = 1{\text{gm}} $
Therefore, $ 660000{\text{mg}} = 660{\text{g}} $
So, we have found out the weight of Kohinoor diamond as $ 660{\text{gm}} $
Now, we need to find out the number of moles of carbon atoms present in it
To calculate the number of moles of carbon atoms, we know that,
12g carbon atoms constitute 1 mole units of carbon atoms
So, we need to find the number of moles in $ 660{\text{gm}} $ of carbon atoms
That is
Number of moles in Kohinoor diamond $ = \dfrac{{660}}{{12}} = 55{\text{ moles}} $
Hence, the number of moles in Kohinoor diamond is 55 moles.

Note
A convenient method of expressing the quantity of a substance is the mole concept. It is possible to break down any measurement into two parts: the numerical magnitude and the units in which the magnitude is expressed. In the field of chemistry, a mole is defined as the amount of a substance that contains exactly $ 6.02214076 \times {10^{23}} $ 'elementary entities' of the given substance. The number $ 6.02214076 \times {10^{23}} $ is commonly referred to as the constant of Avogadro and is often denoted by the ' $ {N_A} $ ' symbol. Atoms, molecules, and other particles can be the fundamental entities that can be represented in moles.