High School

Convert 28.1 grams of CO[tex]_{2}[/tex] into moles.

A. 1.00 moles
B. 1.57 moles
C. 0.996 moles
D. 0.639 moles

Answer :

To convert 28.1 grams of CO2 into moles, you need to use the concept of molar mass. Here's how you can do it step-by-step:

1. Know the Molar Mass of CO2:
The molar mass of carbon dioxide (CO2) is the sum of the atomic masses of its elements. It consists of one carbon atom (with an atomic mass of about 12.01 grams per mole) and two oxygen atoms (with an atomic mass of about 16.00 grams per mole each). Therefore, the molar mass of CO2 is:
[tex]\[
12.01 + 2 \times 16.00 = 44.01 \text{ grams per mole}
\][/tex]

2. Convert Grams to Moles:
To find out how many moles are in a given mass, you divide the mass of the substance by its molar mass. In this case, divide 28.1 grams by the molar mass of CO2:
[tex]\[
\text{Moles of CO2} = \frac{\text{Mass of CO2 in grams}}{\text{Molar mass of CO2}} = \frac{28.1}{44.01}
\][/tex]

3. Calculate:
Performing this division gives you the number of moles:
[tex]\[
0.639 \text{ moles (rounded to three significant figures)}
\][/tex]

Thus, 28.1 grams of CO2 is approximately 0.639 moles.