To determine the number of particles in a substance, you need to use the concept of Avogadro's number and the molar mass of the substance. Avogadro's number (Nā) is approximately 6.022 x 10^23 particles per mole.
First, you need to calculate the number of moles of NaOH using its molar mass. The molar mass of sodium hydroxide (NaOH) is: Na: 22.99 grams/mol O: 16.00 grams/mol H: 1.01 grams/mol
Adding these values together, the molar mass of NaOH is 22.99 + 16.00 + 1.01 = 40.00 grams/mol.
Now, we can calculate the number of moles using the formula: Number of moles = Mass / Molar mass
Number of moles of NaOH = 10.2 grams / 40.00 grams/mol = 0.255 moles
Finally, we can calculate the number of particles (in this case, molecules) by multiplying the number of moles by Avogadro's number: Number of particles = Number of moles Ć Avogadro's number
Number of particles = 0.255 moles Ć 6.022 x 10^23 particles/mol ā 1.536 x 10^23 particles
Therefore, approximately 10.2 grams of NaOH contains about 1.536 x 10^23 particles of NaOH.