Answer:
A (Second)
Explanation:
A second is the base unit of time.
Because the iron in the sand gives the sand a different weight than needed. a lot of people either just need the iron or the sand when mixed it gives the wrong outcome of what was needed.
Molar mass Na = 23 g/mol
23 g ------------- 6.02 x 10²³ atoms
4.56 x 10⁻² g ----- ? atoms
atoms = 4.56 x 10⁻² x ( 6.02 x 10²³ ) / 23
atoms = 2.74 x 10²² / 23
= 1.19 x 10²¹ atoms
hope this helps!
0.9mole of Fe
Explanation:
Given parameters:
Mass of Fe = 50g
Unknown:
Number of moles of iron = ?
Solution:
The number of moles is the particle that contains the avogadro's number of particles.
It is a unit for reporting chemical measurement.
To find the number of moles of a substance;
Number of moles =
Molar mass of Fe= 56g/mol
Number of moles = = 0.9mole of Fe
learn more:
Number of moles brainly.com/question/1841136
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