How Does Mixing Water at Different Temperatures Affect the Final Temperature?

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In summary, the conversation discusses the incorrect answer of 60 degrees as the final temperature when mixing equal masses of water at 20 and 80 degrees. It is pointed out that the final temperature will depend on the temperature of the environment and that the "initial" temperature should be interpreted as the temperature immediately after mixing. The average of the two temperatures is suggested as a method for finding the final temperature, taking into consideration the amount of water at each temperature. The conversation concludes with appreciation for the help and camaraderie among the participants.
  • #1
Dx
Equal masses of water 20C and 80C are mixed. what is the inal temp of the mixture?

I said 60C
why is this incorrect?
Dx
 
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  • #2
It's not correct because 60o is the final (not initial) temperature.
 
  • #3
I see
dx:wink:
 
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  • #4
Originally posted by Dx
Thanks Tom!
dx:wink:
 
  • #5
Once again, DX, be careful of Tom's answers.
The problem with asking someone to give you the answer is that they may just give you a WRONG answer!

It's not correct because 60 degrees is the final (not initial) temperature.
is not correct. You don't know what the "final" temperature will be because you don't know the temperature of the environment. In order to do this problem, you will have to interpret "initial" temperature as the temperature immediately AFTER mixing.

What makes you think the temperature will be 60 degrees? The only way I see that you can get 60 is to subtract 20 from 80. Do you have any reason for that? If the two temperatures had been 60 and 50 would you say that the mixture will be 10 degrees? Does that even make sense?

It should make sense to you that if you mix two things the final temperature will be BETWEEN the two original ones. In fact you should think about finding the average of the two temperatures.
What is the average of 20 and 80 degrees?

You should also think about how you would "average" the temperatures there were more water at one temperature than the other.

Suppose you had 10 grams of water at 20 degrees and 40 grams of water at 80 degrees. ABOUT what do you think the temperature of the mixture would be? How would you calculate it exactly?
 
  • #6
Originally posted by HallsofIvy
Once again, DX, be careful of Tom's answers.
The problem with asking someone to give you the answer is that they may just give you a WRONG answer!


is not correct. You don't know what the "final" temperature will be because you don't know the temperature of the environment. In order to do this problem, you will have to interpret "initial" temperature as the temperature immediately AFTER mixing.

What makes you think the temperature will be 60 degrees? The only way I see that you can get 60 is to subtract 20 from 80. Do you have any reason for that? If the two temperatures had been 60 and 50 would you say that the mixture will be 10 degrees? Does that even make sense?

It should make sense to you that if you mix two things the final temperature will be BETWEEN the two original ones. In fact you should think about finding the average of the two temperatures.
What is the average of 20 and 80 degrees?

You should also think about how you would "average" the temperatures there were more water at one temperature than the other.

Suppose you had 10 grams of water at 20 degrees and 40 grams of water at 80 degrees. ABOUT what do you think the temperature of the mixture would be? How would you calculate it exactly?

Let me see. 20 + 80 = 100 / 2 = 50 average. I think i understand better now Ivy. Thanks! Can I add you as a friend, please? Let me try to work the problem further and if I jave anumore problems ill ask.
Dx :wink:
 
  • #7
Originally posted by HallsofIvy
You should also think about how you would "average" the temperatures there were more water at one temperature than the other.

Actually, I assumed he did average them and that's how he got 60o. I didn't even notice that 60 isn't the average!
 
  • #8
we forgive you this time Tom.
Just teasing, i am glad to see that everyone has each others back. Thanks HallsOfIvy,
I appreciate your help and toms too.
Dx:wink:
 

1. What is heat and how does it relate to equal masses of H20?

Heat is a form of energy that is transferred from one object to another due to a temperature difference. In the case of equal masses of H20, heat is the energy that causes the temperature of the water to increase or decrease.

2. How does the specific heat of H20 affect its temperature when heated?

The specific heat of a substance is the amount of energy required to raise the temperature of 1 gram of the substance by 1 degree Celsius. H20 has a high specific heat, which means it requires a lot of energy to raise its temperature. This means that equal masses of H20 will take longer to heat up compared to other substances with lower specific heats.

3. What is the relationship between mass and temperature in terms of heat?

The relationship between mass and temperature in terms of heat is directly proportional. This means that as the mass of H20 increases, more energy is needed to raise its temperature compared to a smaller mass of H20. Similarly, as the temperature of H20 increases, more energy is needed to raise its mass compared to a lower temperature of H20.

4. How does the heat capacity of H20 affect its ability to retain heat?

The heat capacity of a substance is the amount of heat energy required to raise the temperature of the substance by 1 degree Celsius. H20 has a high heat capacity, meaning it can hold a large amount of heat energy without experiencing a significant change in temperature. This makes it an effective heat retainer, as it can maintain its temperature for a longer period of time compared to substances with lower heat capacities.

5. What are some practical applications of understanding heat and equal masses of H20?

Understanding the relationship between heat and equal masses of H20 has numerous practical applications. This knowledge is important in industries such as cooking and brewing, where precise temperature control is necessary for optimal results. It is also used in heating and cooling systems, as well as in the study of weather patterns and climate change.

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