Question

3. Americans combined drive about 4.0 * 10 miles per day and their vehicles get an average of 20. miles per gallon of fuel used. For each 1.00 kg of gasoline that is burned, about 3.00 kg of CO2 are produced. How many kilograms of CO2 are emitted into the atmosphere each day by cars in the U.S. (Hint: 1 gallon of gas = 3.5 kg gas) (3 pts)

Answer 1

Solution :

Americans combined drive about 4 × 10⁹ miles per day & their vehicles get an average of 20.0 miles per gallon of gasoline (fuel) used, i.e.

For an average 20 miles drive, 1 gallon of gasoline is used.

Thus, for 1 mile of drive, 1/20 gallon of gasoline will be used.

Hence, for 4 × 10⁹ miles of drive :

$\frac{1}{20} \times 4 \times 10^{9}$ gallon of gasoline will be used i.e. 0.2 × 10⁹ gallon of gas.

Now, 1 gallon of a gas = 3.5 kg of a gas.

Thus, 1 gallon of gasoline = 3.5 kg of gasoline.

So, 0.2 × 10⁹ gallon of gasoline = (3.5 × 0.2 × 10⁹) kg of gasoline = 0.7 × 10⁹ kg of gasoline.

Also, according to question,

For 1 kg of gasoline burned, 3 kg of CO_​​2 is produced.

Thus, for 0.7 × 10⁹ kg of gasoline burned :

(0.7 × 3 × 10⁹) kg of CO_{​​​​​2}​ will be produced i.e. 2.1 × 10⁹ kg of

CO_{​​​​​2} .

Thus, answer is 2.1 × 10⁹ kg of CO_{​​​​​2} will be emitted into atmosphere each day by cars in U.S. .