Question

How many atoms of Na are present in its 200mg?​

Answer 1

Answer:

How many atoms are present in 2g of Na?

To calculate the number of atoms in two moles of sodium, use dimensional analysis. 2.0 moles Na x 6.022⋅1023g1mol=1.20⋅1024 atoms of Na

Explanation:

Answer 2

Given - Mass of sodium = 200 mg

Find - Atoms of sodium

Solution - Firstly calculating number of moles of sodium.

Molar mass of sodium = 23 gram/mole

Mass of sodium in grams = 0.2 grams

Number of moles = mass/molar mass

Number of moles = 0.2/23

Number of moles of 200 mg sodium = 0.009

Now, 1 mole has atoms equal to Avogadro's number. Avogadro's number is 6.02*10²³ atoms

So, 0.009 moles will have = 6.02*10²³*0.009

Number of atoms = 5.6*10²¹

Thus, atoms in 200 mg sodium are 5.6*10²¹