Question

How many total atoms are in 0.170 g of p2o5?

Answer 1

To find the total number of atoms in 0.170 g of P₂O₅, we first determine the moles of P₂O₅ from its mass and molar mass, then multiply by the number of atoms per molecule, and finally use Avogadro's number to find there are approximately 5.04 x 10²¹ total atoms.

Step-by-step explanation:

To calculate the total number of atoms in 0.170 g of P₂O₅ (phosphorus pentoxide), we first need to determine the number of moles of P₂O₅ this mass corresponds to. We use the molar mass of P₂O₅, which is 141.94 grams per mole (g/mol).

First, calculate the moles of P₂O₅ :

(0.170 g) / (141.94 g/mol) = 0.001197 moles of P₂O₅.

Next, since one molecule of P₂O₅ consists of 2 phosphorus atoms and 5 oxygen atoms, a single mole of P₂O₅ contains 7 moles of atoms (2 moles of P and 5 moles of O).

Now, calculate the total number of atoms:
0.001197 moles of P₂O₅ * 7 moles of atoms/mole of P₂O₅ = 0.008379 moles of atoms.

To convert moles of atoms to the number of atoms, use Avogadro's number, which is 6.022 x 10²³ atoms per mole:

0.008379 moles of atoms * (6.022 x 10²³ atoms/mole) = 5.04 x 10²¹ total atoms.

Answer 2

7.20594 x 10^20

First you must determine how many moles of P3O5 you have. This is done by using the formula
Number of moles (n) = mass in grams of substance (m) /divided by/ Molar mass (M) [this is the sum of the atomic mass of all atoms in the compound]

n = 0.170 / P (31 x 2) + O (16 x 5)
n = 0.170 / 142
n = 0.001197 moles

Then you use avagadros number 6.02 x10^23 this is the number of atoms in one mole of any substance. Since you have 0.001197 moles you multiply the number of moles by avagadros number

0.001197 x (6.02 x 10^23)
= 7.20594 x 10^20 atoms