MHB Heat Capacity: Mixing 100g Water @2C & 50g Ice @-4C

AI Thread Summary
Mixing 100g of water at 2°C with 50g of ice at -4°C requires calculating the heat exchanges to determine the final temperature. The heat of fusion for ice is 334 kJ/kg, which is crucial for determining how much ice melts or water freezes. The four scenarios for the final state include all ice melting, some ice melting, some water freezing, or all water freezing, with specific conditions for each case. The energy calculations involve heating the ice to 0°C, melting it, and heating or cooling the water accordingly. Understanding these energy exchanges is essential for solving the problem accurately.
Raerin
Messages
46
Reaction score
0
If 100g of water at 2 degrees Celsius is mixed with 50g of ice a -4 degrees Celsius, what is the final temperature of water? It also says that I need the heat of fusion of the ice to solve it, which I have found to be 334 kj/kg. I don't know what to do with the heat of fusion. Also, how do I convert 344 kj/kg to j/g? Is it still 334?
 
Mathematics news on Phys.org
Raerin said:
how do I convert 344 kj/kg to j/g? Is it still 334?
Yes.

Raerin said:
If 100g of water at 2 degrees Celsius is mixed with 50g of ice a -4 degrees Celsius, what is the final temperature of water? It also says that I need the heat of fusion of the ice to solve it, which I have found to be 334 kj/kg. I don't know what to do with the heat of fusion.
There are four options:

(1) all ice will melt
(2) some ice will melt
(3) some water will freeze
(4) all water will freeze

In cases (2) and (3) the resulting temperature of the mixture is 0 degrees Celsius.

Consider the following energies.

$Q_1$ heats 50g of ice from -4°C to 0°C.

$Q_2$ melts 50g of ice at 0°C.

$Q_3$ melts 100g of ice at 0°C, or is produced when 100g of water freezes.

$Q_4$ heats 100g of water from 0°C to 2°C, or is produces when 100g of water cools from 2°C to 0°C.

Then the options above take place under the following conditions.

(1) $Q_1+Q_2<Q_4$
(2) $Q_1<Q_4<Q_1+Q_2$
(3) $Q_4<Q_1<Q_4+Q_3$
(4) $Q_3+Q_4<Q_1$

$Q_2$ and $Q_3$ are found by multiplying heat of fusion by mass.
 
Suppose ,instead of the usual x,y coordinate system with an I basis vector along the x -axis and a corresponding j basis vector along the y-axis we instead have a different pair of basis vectors ,call them e and f along their respective axes. I have seen that this is an important subject in maths My question is what physical applications does such a model apply to? I am asking here because I have devoted quite a lot of time in the past to understanding convectors and the dual...
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. In Dirac’s Principles of Quantum Mechanics published in 1930 he introduced a “convenient notation” he referred to as a “delta function” which he treated as a continuum analog to the discrete Kronecker delta. The Kronecker delta is simply the indexed components of the identity operator in matrix algebra Source: https://www.physicsforums.com/insights/what-exactly-is-diracs-delta-function/ by...

Similar threads

Back
Top