A bowl of 471 g of water is placed in a microwave oven that puts out 591 watts (J/s). How long would it take in seconds to increase the temperature of the water from 12.0oC to 53.3oC? Use SF.
I'm not really sure how to do this, so any help would be appreciated!
Okay thanks. I got the answer to be 81427.33. SF just means significant figures.
is that right? With significant figures it's 81000.
To solve this problem, we can use the equation:
Q = mcΔT
Where:
Q represents the heat absorbed (in Joules)
m represents the mass of the water (in grams)
c represents the specific heat capacity of water (in J/g°C)
ΔT represents the change in temperature (in °C)
To find the heat absorbed, we can rearrange the equation as follows:
Q = mcΔT
Q = (mass of water) x (specific heat capacity of water) x ΔT
First, we need to convert the mass of water from grams to kilograms:
471 g = 471/1000 kg = 0.471 kg
Next, we need to convert the temperatures from Celsius to Kelvin. To do this, we add 273.15 to each temperature:
12.0°C + 273.15 = 285.15 K
53.3°C + 273.15 = 326.45 K
Now we can substitute the values into the equation:
Q = (0.471 kg) x (4.18 J/g°C) x (326.45 K - 285.15 K)
Next, we need to calculate the time it takes for the microwave oven to deliver this amount of heat to the water. We can use the equation:
Power = Energy / Time
Rearranging the equation to solve for time, we get:
Time = Energy / Power
First, let's calculate the energy:
Energy (in Joules) = Q
Now, we need to convert the power from watts (Joules per second) to Joules:
Power (in Joules) = 591 watts x time
Finally, we can substitute the values into the equation to find the time:
Time (in seconds) = Energy (in Joules) / Power (in Joules)
Now we can calculate the time it takes to increase the temperature of the water.
power*time=energy=mass*specificheat*(53.3-12)
solve for time
I have no idea what you mean by SF