Answer : The correct option is, (D)
Solution :
Formula used :
where,
Q = heat released = -1300 J
m = mass of water = 40 g
c = specific heat of water =
= final temperature = ?
= initial temperature =
Now put all the given values in the above formula, we get the final temperature of water.
Therefore, the final temperature of the water is,
Answer:
Explanation:
Rate laws are mathematical expressions which define the relationship that exists between the rate of a chemical reaction and the concentration of the reacting components. Rate laws take the following form:
...
where k = rate constant
[A], [C] and [C] represent the molar concentrations of the reactants
k, x, y, and z are determined experimentally by observing how the rate of reaction changes with the concentrations of the reactants.
If x=1, the reaction is first order for [A]. Also, if y=2, the reaction is second order for [B] and so on...
The overall order of the reaction is the sum of the orders with respect to each reactant. Therefore, the overall order of the reaction is x+y+z.
(1) The quantity of heat required to melt 175 g Cu is 35.88 kJ.
(2) The substance that releases 21.2 kJ of energy when 1.42 mol of it freezes is iron.
<h3>What is heat of fusion?</h3>Heat of fusion is the energy required to melt 1 mole of a substance.
<h3>What is heat of vaporization?</h3>The heat energy required to vaporize 1 mole of a substance has been heat of vaporization.
Heat of fusion of copper (Cu) is given as 13 kJ/mol
Number of moles of 175 g of copper = 175/63.5 = 2.76 moles
Q = nΔH
Q = 2.76 mol x 13 kJ/mol = 35.88 kJ
Thus, the quantity of heat required to melt 175 g Cu is 35.88 kJ.
<h3>Heat of fusion of the substance</h3>ΔH(fus) = Q/n
where;
ΔH(fus) = 21.2 kJ / 1.42 mol
ΔH(fus) = 14.93 kJ/mol
From the table the substance with latent heat of fusion of 14.9 kJ/mol is iron.
Thus, the substance that releases 21.2 kJ of energy when 1.42 mol of it freezes is iron.
Learn more heat of fusion here: brainly.com/question/87248
#SPJ1
