Answer:
1.26*10²³ particles are present in 12.47 grams of NaCl
Explanation:
Avogadro's Number or Avogadro's Constant is called the number of particles that make up a substance (usually atoms or molecules) and that can be found in the amount of one mole of said substance. Its value is 6.023 * 10²³ particles per mole. The Avogadro number applies to any substance.
So, first of all you must know the amount of moles that represent 12.47 grams of NaCl. For that it is necessary to know the molar mass.
You know:
- Na: 23 g/mole
- Cl: 35.45 g/mole
So the molar mass of NaCl is: 23 g/mole + 35.45 g/mole= 58.45 g/mole
Now you apply a rule of three as follows: if 58.45 grams are present in 1 mole of NaCl, 12.47 grams in how many moles will they be?

moles= 0.21
You apply a rule of three again, knowing Avogadro's number: if in 1 mole of NaCl there are 6,023 * 10²³ particles, in 0.21 moles how many particles are there?

number of particles= 1.26*10²³
<u><em>1.26*10²³ particles are present in 12.47 grams of NaCl</em></u>
<u><em></em></u>
<u>We are given:</u>
Mass of NaCl in the given solution = 22.3 grams
Volume of the given solution = 2 L
<u></u>
<u>Number of Moles of NaCl:</u>
We know that the number of moles = Given mass / Molar mass
Number of moles = 22.3 / 58.44 = 0.382 moles
<u></u>
<u>Molarity of NaCl in the Given solution:</u>
We know that Molarity of a solution = Moles of Solute / Volume of Solution(in L)
Molarity = 0.382 / 2
Molarity = 0.191 M
<em />
Acid + alkali ------> salt + water
2KOH + H2SO4 ------> K2SO4 + 2H2O
Hope it helped!