How Much Steam is Needed to Raise Water Temperature from 20°C to 50°C?

AI Thread Summary
To raise the temperature of 200g of water from 20°C to 50°C in a 40g copper calorimeter, the specific heat of water (4.186 J/g°C) is used to calculate the heat required, resulting in 25,116 J. The specific heat of copper is not needed for this calculation as it does not participate in the heat transfer. To find the amount of steam needed, the heat of vaporization (2260 J/g) is applied, leading to the conclusion that 11.11 grams of steam must be condensed. This calculation effectively demonstrates the relationship between heat transfer and phase change in thermodynamics.
cogs24
Messages
30
Reaction score
0
hi guys, i have the following question to answer:

a 40g copper calorimeter contains 200g of water at 20 degrees celsius, it asks how much stam must be condensed in order to achieve a final temperature of 50 degrees celsius.
I was just wondering what formula to use?, and do i need to know the specific heat of copper?
 
Physics news on Phys.org
Yes, using the specific heat of copper and water, calculate how much heat is gained as the temperature rises from 20 to 50C. The equation for the calorimeter is simply heat gain equals specific heat times delta-T. For condesing steam, you have two parts: the heat loss from condensing the steam and the heat loss from cooling it from 100C to 50C.
 


To answer this question, we can use the formula for heat transfer: Q = mcΔT, where Q is the heat transferred, m is the mass, c is the specific heat, and ΔT is the change in temperature.

In this case, we are trying to find the amount of steam (Q) needed to achieve a final temperature of 50 degrees Celsius. We know the mass of water (200g) and the change in temperature (50-20 = 30 degrees Celsius). We also need to know the specific heat of water, which is 4.186 J/g°C.

However, we do not need to know the specific heat of copper in this case because the calorimeter is not involved in the heat transfer process. It is simply used to contain the water.

So, we can set up the equation as follows:

Q = (200g)(4.186 J/g°C)(30°C)
Q = 25,116 J

This is the amount of heat needed to raise the temperature of the water from 20 degrees Celsius to 50 degrees Celsius. Now, we need to convert this heat into the amount of steam needed.

We can use the formula for heat of vaporization: Q = mL, where Q is the heat transferred, m is the mass, and L is the heat of vaporization.

In this case, we know the heat of vaporization of water is 2260 J/g. So, we can rearrange the equation to solve for mass:

m = Q/L
m = (25,116 J)/(2260 J/g)
m = 11.11 g

Therefore, 11.11 grams of steam must be condensed in order to achieve a final temperature of 50 degrees Celsius. I hope this helps!
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'Collision of a bullet on a rod-string system: query'
In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top