Question

How many atoms are present in 48.60 g of mg?

Answer 1

A genuine use of Avogadro’s number applies to the notorious illustration of analyzing the thickness of what gauges more: a huge load of quill or a huge load of something substantial like blocks or metal loads.

Complete answer:
In order to go from mass of magnesium to atoms of magnesium, we have to do two things:
Convert mass of Mg to moles of Mg using the molar mass of Mg as a conversion factor
Convert moles of Mg to atoms of Mg using Avogadro's number (6.02$\times$ $10^23$) as a conversion factor
Step 1:
Before we start, I should note that the molar mass of Mg is 24.31gmol. We can go from mass to moles using dimensional analysis. The key to dimensional analysis is understanding that the units that you don't need any more cancel out, leaving the units that are desired:
$48.60g \times \dfrac{{1mol}}{{24.31g}} = 2.00$
Step 2:
We'll use this relationship:
$\dfrac{{6.02 \times {{10}^{23}}}}{{1mol}}$
Using the moles of Mg that we just obtained, we can use Avogadro’s number to perform dimensional analysis in order to cancel out units of mol to end up with atoms of Mg:
$2.00mol \times \dfrac{{6.02 \times {{10}^{24}}}}{{1mol}} = 1.204 \times {10^{24}}atoms$
Prior to deciding nuclear mass, you need to look into the components on the intermittent table and note their nuclear mass numbers under the component's substance image. Unadulterated components have a nuclear mass that is additionally the molar mass or measure of grams per mole.

Note: Iotas are tiny compared with the size of human existence. Researchers utilize a unit called a mole to depict enormous amounts of iotas and other little things. One mole is equivalent to $6.022 \times {10^{23}}$ particles.