Calculate Heat of Reaction for 50g of Water at 80°C

In summary, the question is asking for the amount of heat absorbed by the room temperature water, which is 50g, when 50g of hot water at 80°C is added to it in a bowl and the temperature in the bowl increases from 25°C to 48°C. The correct equation to use is Q = (50g)(4.18 J/(g*k))(48-25), as the mass of the room temperature water is 50g. The discussion also clarifies that the mass of the room temperature water is indeed 50g, and not 100g.
  • #1
aDVnatgae
4
0

Homework Statement


Hi
Lets say I heat 50g of water to 80°C. I take another 50g of room temperature water and put it in a bowl.

Then I add this 50g of heat water to the bowl, the temperature in the bowl goes from 25°C to 48°C.

What is the amount of heat absorbed by the room temperature water?


Homework Equations



Is it
Q = (50g)(4.18 J/(g*k))(48-25)
or
Q = (100g)(4.18 J/(g*k))(48-25)

The Attempt at a Solution



Do you add the solution of water in the mass or just use 50g=mass in the equation?
 
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  • #2
aDVnatgae said:
What is the amount of heat absorbed by the room temperature water?

What is the mass of the room temperature water? 50g or 100g?
 
  • #3
Borek said:
What is the mass of the room temperature water? 50g or 100g?

I add the 50g of hot water to 50g of water in the bowl. Wondering when calculation the
Q=mc(dT)
should the mass be 100 or 50
 
  • #4
You have 50 g of the room temperature water and 50 g of hot water. What is the mass of the room temperature water?

This is like one of those stupid joke questions kids ask - answer is so obvious nobody sees it.

Yes, it is THAT simple.
 
  • #5
Borek said:
You have 50 g of the room temperature water and 50 g of hot water. What is the mass of the room temperature water?

This is like one of those stupid joke questions kids ask - answer is so obvious nobody sees it.

Yes, it is THAT simple.

What is the mass of the room temperature water?
answer is 50g
 
  • #6
Borek said:
You have 50 g of the room temperature water and 50 g of hot water. What is the mass of the room temperature water?

This is like one of those stupid joke questions kids ask - answer is so obvious nobody sees it.

Yes, it is THAT simple.

K. What I am asking to you is when I add hot water in the bowl to temperature of bowl changes from 25°C to 48°C. The total mass of water in the bowl is 100g.

What is the amount of heat absorbed by the room temperature water?
So do I use 50g or 100g as a mass?
 
  • #7
There is 50 g of the room temperature water, so 50 g of the room temperature water can absorb a heat.

Imagine you have not mixed these samples of water, but they were isolated by a thin metal sheet so that they could not mix, but the heat could easily flow. Final temperature is identical in both cases, but it should be obvious why there is 50 g of the room temperature water absorbing heat.

Note that so far we were all the time discussing exactly the same problem, you just couldn't make a connection. If there is 50 g of the room temperature water there is 50 g of water that can absorb heat.
 

FAQ: Calculate Heat of Reaction for 50g of Water at 80°C

What is the formula for calculating the heat of reaction for 50g of water at 80°C?

The formula for calculating the heat of reaction for 50g of water at 80°C is Q = mCpΔT, where Q is the heat of reaction, m is the mass of the substance (in this case, water), Cp is the specific heat capacity of water, and ΔT is the change in temperature.

How do I determine the specific heat capacity of water for this calculation?

The specific heat capacity of water is a constant value and can be found in reference tables. The specific heat capacity of water is 4.184 J/g°C.

What is the mass of water needed for this calculation?

The question states that the mass of water is 50g, so that is the mass that should be used in the calculation.

What units should be used for the temperature in this calculation?

The units for temperature should be in degrees Celsius (°C) for this calculation. It is important to use consistent units throughout the calculation.

Can this formula be used for any substance or only for water?

This formula can be used for any substance, as long as the specific heat capacity for that substance is known. However, it is important to note that the specific heat capacity may vary for different substances.

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