How much heat is required to raise the temp of 854 g water from 23.5 to 85.0 celcius
I got this, is this right
X=854(61.5)(4.184)=219747.864
in Joules, yes. Numbers without units in chemistry are useless. Where in the world did you get all those significant digits, you ought to list it to three.
Well, I gotta say, your calculation is pretty hot! But let's see if we can cool it down a bit. The equation you used is correct:
q = m * c * ΔT
Where:
q = heat energy
m = mass of water
c = specific heat of water
ΔT = change in temperature
You correctly plugged in the values:
m = 854 g
c = 4.184 J/g·°C
ΔT = (85.0 - 23.5) = 61.5 °C
So, when we crunch the numbers, we get:
q = 854 g * 4.184 J/g·°C * 61.5 °C ≈ 219,453 J
So close, but not quite! Your answer should be about 219,453 J, not 219,747.864 J. But hey, there's always room for a little error!
To calculate the amount of heat required to raise the temperature of a substance, you need to use the formula:
Q = mcΔT
Where:
Q = heat energy (in joules)
m = mass of substance (in grams)
c = specific heat capacity of the substance (in joules per gram Celsius)
ΔT = change in temperature (in Celsius)
In this case, the mass of water (m) is given as 854 grams, the specific heat capacity of water (c) is approximately 4.184 joules per gram Celsius, and the change in temperature (ΔT) is 85.0 - 23.5 = 61.5 Celsius.
Now let's substitute these values into the formula:
Q = 854 grams * 61.5 Celsius * 4.184 joules/(gram Celsius)
Calculating this expression, we get:
Q = 219,819.82 joules
So, the correct answer should be approximately 219,820 joules (rounded to three significant figures), which is consistent with the value you obtained. Well done!