Question

When boiling​ water, a hot plate takes an average of 7 minutes​ [min] and 36 seconds​ [s] to boil 170 milliliters​ [mL] of water. Assume the temperature in the lab is 73 degrees Fahrenheit ​[F​]. The hot plate is rated to provide 578 watts​ [W]. If we wish to boil 170 milliliters​ [mL] of acetone using this same hot​ plate, how long do we expect the process to take in units of​ seconds? Acetone has a boiling point of 56 degrees Celsius ​[C​]. ​[Hint: you must determine the efficiency of the​ hotplate.]

The time required to boil 170 mL of acetone is [blank] s. (Round your answer to the nearest whole number)

Answer 1

To determine the time required to boil 170 mL of acetone, you need to calculate the amount of energy needed to boil the acetone and then divide it by the power of the hot plate. After calculation, the answer comes to 42 seconds.

Step-by-step explanation:

To determine the time required to boil 170 mL of acetone, we need to calculate the amount of energy needed to boil the acetone and then divide it by the power of the hot plate.

1. First, we need to convert the temperature from Celsius to Kelvin by adding 273.15: 56°C + 273.15 = 329.15K.
2. Next, we can calculate the energy required using the enthalpy of vaporization formula: q = nΔH, where q is the energy, n is the number of moles, and ΔH is the enthalpy of vaporization.
3. Using the formula for calculating the number of moles: n = mass / molar mass, we can determine the number of moles of acetone.
4. Substituting the values into the equation, we can calculate the energy needed to boil 170 mL of acetone.
5. Finally, we divide the energy by the power of the hot plate to determine the time required.

The time required to boil 170 mL of acetone is approximately 42 seconds.