- #1
mcnivvitz
- 7
- 0
The problem:
On a hot summer day, you decide to make some iced tea. First, you brew 1.50 L of hot tea and leave it to steep until it has reached a temperature of T_tea = 75.0 C. You then add 0.975 kg of ice taken from the freezer at a temperature of T_ice = 0 C. By the time the mix reaches equilibrium, all of the ice has melted. What is the final temperature T_f of the mixture?
For the purposes of this problem, assume that the tea has the same thermodynamic properties as plain water.
The specific heat of water is = 4190.
The heat of fusion of ice is = 3.33×105 .
The density of the tea is = 1.00 .
My attempt:
I wrote the following expression to find T_f:
T_f = (m_tea*c*T_tea + m_ice*c*T_ice - L_f*m_ice) / (cm_tea + cm_ice)
I'm pretty sure this is right, but when I plug in the variables, I get:
(1.5*4190*75 - .975*3.33e5) / (4190*1.5 + .975*2050) = 17.71 C
17 degrees seems like a reasonable answer but it's not right. What could I be doing wrong?
Thanks.
On a hot summer day, you decide to make some iced tea. First, you brew 1.50 L of hot tea and leave it to steep until it has reached a temperature of T_tea = 75.0 C. You then add 0.975 kg of ice taken from the freezer at a temperature of T_ice = 0 C. By the time the mix reaches equilibrium, all of the ice has melted. What is the final temperature T_f of the mixture?
For the purposes of this problem, assume that the tea has the same thermodynamic properties as plain water.
The specific heat of water is = 4190.
The heat of fusion of ice is = 3.33×105 .
The density of the tea is = 1.00 .
My attempt:
I wrote the following expression to find T_f:
T_f = (m_tea*c*T_tea + m_ice*c*T_ice - L_f*m_ice) / (cm_tea + cm_ice)
I'm pretty sure this is right, but when I plug in the variables, I get:
(1.5*4190*75 - .975*3.33e5) / (4190*1.5 + .975*2050) = 17.71 C
17 degrees seems like a reasonable answer but it's not right. What could I be doing wrong?
Thanks.