<u>answer</u> 1<u> </u><u>:</u>
Law of conservation of momentum states that
For two or more bodies in an isolated system acting upon each other, their total momentum remains constant unless an external force is applied. Therefore, momentum can neither be created nor destroyed.
<u>answer</u><u> </u><u>2</u><u>:</u><u> </u>
When a substance is provided energy<u> </u>in the form of heat, it's temperature increases. The extent of temperature increase is determined by the heat capacity of the substance. The larger the heat capacity of a substance, the more energy is required to raise its temperature.
When a substance undergoes a FIRST ORDER phase change, its temperature remains constant as long as the phase change remains incomplete. When ice at -10 degrees C is heated, its temperature rises until it reaches 0 degrees C. At that temperature, it starts melting and solid water is converted to liquid water. During this time, all the heat energy provided to the system is USED UP in the process of converting solid to the liquid. Only when all the solid is converted, is the heat used to raise the temperature of the liquid.
This is what results in the flat part of the freezing/melting of condensation/boiling curve. In this flat region, the heat capacity of the substance is infinite. This is the famous "divergence" of the heat capacity during a first order phase transition.
There are certain phase transitions where the heat capacity does not become infinitely large, such as the process of a non-magnetic substance becoming a magnetic substance (when cooled below the so-called Curie temperature).
The answer is D. element
It's not a mixture, just a pure element. Copper (Cu) is found on the Periodic Table of the Elements, where only ELEMENTS are organized.
Answer : The enthalpy change for the process is 52.5 kJ/mole.
Explanation :
Heat released by the reaction = Heat absorbed by the calorimeter + Heat absorbed by the solution
![q=[q_1+q_2]](https://tex.z-dn.net/?f=q%3D%5Bq_1%2Bq_2%5D)
![q=[c_1\times \Delta T+m_2\times c_2\times \Delta T]](https://tex.z-dn.net/?f=q%3D%5Bc_1%5Ctimes%20%5CDelta%20T%2Bm_2%5Ctimes%20c_2%5Ctimes%20%5CDelta%20T%5D)
where,
q = heat released by the reaction
= heat absorbed by the calorimeter
= heat absorbed by the solution
= specific heat of calorimeter = 
= specific heat of water = 
= mass of water or solution = 
= change in temperature = 
Now put all the given values in the above formula, we get:
![q=[(12.1J/^oC\times 6.1^oC)+(100.0g\times 4.18J/g^oC\times 6.1^oC)]](https://tex.z-dn.net/?f=q%3D%5B%2812.1J%2F%5EoC%5Ctimes%206.1%5EoC%29%2B%28100.0g%5Ctimes%204.18J%2Fg%5EoC%5Ctimes%206.1%5EoC%29%5D)
Now we have to calculate the enthalpy change for the process.
where,
= enthalpy change = ?
q = heat released = 2626.61 J
n = number of moles of copper sulfate used = 
Therefore, the enthalpy change for the process is 52.5 kJ/mole.
