Video Transcript
Which of the following would
usually be measured in moles? (A) The number of atoms in an
object. (B) The number of any types of
parts in any object.
This question asks us what is more
common to measure in moles, the number of atoms or the number of any types of part
in any object.
To be able to answer accurately,
let’s remember that the amount of substance is the number of equivalent parts that
an object made from a single substance consists of. The most commonly used equivalent
parts that are counted in moles are atoms or molecules. Different atoms of the same element
are for most purposes considered completely equivalent to each other. In the SI system, the base unit of
mole refers to a specific number of equivalent parts. This number is 6.02214076 times 10
to the 23. One mole of a substance contains
this number of equivalent parts.
Now, we could think that answer (B)
is correct because it tells us any type of parts of an object. But it is not true because the
parts have to be equivalent to each other. We have said previously that this
number usually refers to atoms and molecules. So, the correct answer is option
(A), the number of atoms in an object.
