Select the correct answer.

How many atoms of N are in 137.0 grams of [tex]$N_2O_3$[/tex]?

A. [tex]$1.085 \times 10^{23}$[/tex]
B. [tex][tex]$1.802 \times 10^{23}$[/tex][/tex]
C. [tex]$5.985 \times 10^{23}$[/tex]
D. [tex]$2.171 \times 10^{24}$[/tex]
E. [tex][tex]$3.604 \times 10^{24}$[/tex][/tex]



Answer :

To find the number of nitrogen atoms in 137.0 grams of [tex]\(N_2O_3\)[/tex], we need to follow these steps:

1. Determine the molar mass of [tex]\(N_2O_3\)[/tex]:
The molar mass of [tex]\(N_2O_3\)[/tex] is given as 108.02 g/mol.

2. Calculate the number of moles of [tex]\(N_2O_3\)[/tex]:
Using the formula:
[tex]\[ \text{Number of moles} = \frac{\text{Mass (grams)}}{\text{Molar mass (g/mol)}} \][/tex]
[tex]\[ \text{Number of moles of } N_2O_3 = \frac{137.0 \text{ grams}}{108.02 \text{ g/mol}} = 1.2682836511757083 \text{ moles} \][/tex]

3. Determine the number of molecules of [tex]\(N_2O_3\)[/tex]:
Using Avogadro's number (approximately [tex]\(6.022 \times 10^{23}\)[/tex] molecules/mol), we calculate:
[tex]\[ \text{Number of molecules of } N_2O_3 = 1.2682836511757083 \text{ moles} \times 6.022 \times 10^{23} \text{ molecules/mol} = 7.637604147380116 \times 10^{23} \text{ molecules} \][/tex]

4. Calculate the number of nitrogen atoms in the sample:
Each molecule of [tex]\(N_2O_3\)[/tex] contains 2 nitrogen atoms. Therefore, we multiply the number of molecules by 2:
[tex]\[ \text{Number of nitrogen atoms} = 7.637604147380116 \times 10^{23} \text{ molecules} \times 2 = 1.5275208294760232 \times 10^{24} \text{ nitrogen atoms} \][/tex]

5. Identify the closest answer option:
We compare the calculated number of nitrogen atoms [tex]\(1.5275208294760232 \times 10^{24}\)[/tex] with the provided answer choices:
- A. [tex]\(1.085 \times 10^{23}\)[/tex]
- B. [tex]\(1.802 \times 10^{23}\)[/tex]
- C. [tex]\(5.985 \times 10^{23}\)[/tex]
- D. [tex]\(2.171 \times 10^{24}\)[/tex]
- E. [tex]\(3.604 \times 10^{24}\)[/tex]

The closest option to [tex]\(1.5275208294760232 \times 10^{24}\)[/tex] is D. [tex]\(2.171 \times 10^{24}\)[/tex].

Therefore, the correct answer is:
[tex]\[ \boxed{2.171 \times 10^{24}} \][/tex]