Question

calculate the total number of ions in 0.585g of sodium chloride

Answer 1

Molecular Weight of NaCl= 23+35.5=58.5g per mole { as atomic mass of sodium = 23g per mole and atomic mass of chlorine atom is 35.5 g per mole }
Which means mass of 1 mole of NaCl = 58.5g 
Or 
58.5 g of NaCl contains = 1 mole of NaCl molecule
⇒⇒ 1g of NaCl contains = (1/ 58.5) mole of NaCl molecules.
5.58g  of NaCl contains = (1×× 5.58/58.5) mole of NaCl molecules.
= 0.1 mole
Each molecule of NaCI contains one Na+ ion and one Cl- ion = 2 ions

Total number of ions in 0.1 mole of NaCI = 2 x 0.1 = 0.2 moles
As 1 mole = 6.022 ×1023 particles
Therefore,
No. of ions present in 0.1 mole = 0.2 ×  6.023 × 1023
= 1.2044 ×1023 ions

Answer 2

Answer:

According to given data,

5.85 g of NaCl=

58.5

5.85

=0.1 moles of NaCl particle

Each NaCl particle contains 2 ions Na

+

and Cl

−

⇒ Total moles of ions =0.1×2 =0.2 moles

No. of ions =0.2×6.022×10

23

=1.2042×10

23

ions