Final answer:
To find the number of moles of CO2 in the balloon, we use the ideal gas law and calculate that there are approximately 0.00115 moles of CO2, which rounds to 0.001 moles, corresponding to answer choice A.
Step-by-step explanation:
The question asks how many moles of CO2 are contained in a balloon with a volume of 28.3 cm3 at 25.0°C and 1.001 atm. To solve this, we can use the ideal gas law equation PV = nRT, where P is the pressure in atmospheres, V is the volume in liters, n is the number of moles, R is the ideal gas constant (0.0821 atm·L/mol·K), and T is the temperature in Kelvin.
First, convert the volume from cm3 to liters (1 L = 1000 cm3) and the temperature from °C to K (T(K) = T(°C) + 273.15). The volume in liters then becomes 0.0283 L and the temperature is 298.15 K.
Then using the ideal gas law equation:
PV = nRT
Substitute the values:
(1.001 atm)(0.0283 L) = n(0.0821 atm·L/mol·K)(298.15 K)
Solve for n (number of moles):
n = (1.001 atm)(0.0283 L) / (0.0821 atm·L/mol·K)(298.15 K) ≈ 0.00115 moles
This value, when rounded to three significant digits gives us 0.001 moles of CO2, which corresponds to answer choice A.