Answer:

Explanation:
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In this case, since it is observed that hot cadmium is placed in cold water, we can infer that the heat released due to the cooling of cadmium is gained by the water and therefore we can write:

Thus, we insert mass, specific heat and temperatures to obtain:

In such a way, since the specific heat of cadmium and water are respectively 0.232 and 4.184 J/(g °C), we can solve for the equilibrium temperature (the final one) as shown below:

Now, we plug in to obtain:

NOTE: since the density of water is 1g/cc, we infer that 25.00 cc equals 25.00 g.
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Well you are at a 86% so t<span>his is considered a "B" grade on an average grade scale. If you take 50 points we would need to know the Total point you could have got in that class to be able to see how much a percent was the assignment work and then take that percentage of the assignment and subtract it from the 86% to see where on the scale you would fall in after the assignment points were taken off. Hope this helps :)
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Answer: Th enthalpy of combustion for the given reaction is 594.244 kJ/mol
Explanation: Enthalpy of combustion is defined as the decomposition of a substance in the presence of oxygen gas.
W are given a chemical reaction:



To calculate the enthalpy change, we use the formula:

This is the amount of energy released when 0.1326 grams of sample was burned.
So, energy released when 1 gram of sample was burned is = 
Energy 1 mole of magnesium is being combusted, so to calculate the energy released when 1 mole of magnesium ( that is 24 g/mol of magnesium) is being combusted will be:

The balanced chemical reaction is:
N2 + 3H2 = 2NH3
We are given the amount of ammonia formed
from the reaction. This is where we start our calculations.
0.575 g NH3 (1 mol NH3 / 17.03 g NH3) (3 mol
H2 / 2 mol NH3) ( 2.02 g H2 / 1 mol H2) = 0.10 g H2