You can put this solution on YOUR website! Chromium has many isotopes
51.99 gm = 1 mole
1 mole contains 6.022 * 10^23 atoms
one has mass number 51.99
51.99 gm of chromium contains 6.022 * 10^23 atoms
In any and every chemical element, there is one and only one atom.
It is why such an entity is called "an element".
More complicated entities in Chemistry are "molecules".
In his post, @mananth gave the answer to other question - not to the question posed in the post.
It is not prohibited to answer another question,
but in this case, it is EXCEPTED that the change of the question
is explicitly motivated, explicitly justified and explicitly expressed.
It is a GOOD style of making conversations and writing explanations in Math.
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