<h3>
Answer:</h3>
1031.4 Calories.
<h3>
Explanation:</h3>
We are given;
Mass of the copper metal = 50.0 g
Initial temperature = 21.0 °C
Final temperature, = 75°C
Change in temperature = 54°C
Specific heat capacity of copper = 0.382 Cal/g°C
We are required to calculate the amount of heat in calories required to raise the temperature of the copper metal;
Quantity of heat is given by the formula,
Q = Mass × specific heat capacity × change in temperature
= 50.0 g × 0.382 Cal/g°C × 54 °C
= 1031.4 Calories
Thus, the amount of heat energy required is 1031.4 Calories.
Answer: The half-reactions represents reduction are as follows.
Explanation:
A half-reaction where addition of electrons take place or a reaction where decrease in oxidation state of an element takes place is called reduction-half reaction.
For example, the oxidation state of Cr in
is +6 which is getting converted into +3, that is, decrease in oxidation state is taking place as follows.

Similarly, oxidation state of Mn in
is +7 which is getting converted into +2, that is, decrease in oxidation state is taking place as follows.

Thus, we can conclude that half-reactions represents reduction are as follows.
C.
Explanation:
As a pendulum swings from its highest to its lowest position along an arc, what happens to its kinetic energy and potential energy? The potential energy decreases while the kinetic energy increases.
<u>Answer:</u> The fugacity coefficient of a gaseous species is 1.25
<u>Explanation:</u>
Fugacity coefficient is defined as the ratio of fugacity and the partial pressure of the gas. It is expressed as 
Mathematically,

Partial pressure of the gas is expressed as:

Putting this expression is above equation, we get:

where,
= fugacity coefficient of the gas
= fugacity of the gas = 25 psia
= mole fraction of the gas = 0.4
P = total pressure = 50 psia
Putting values in above equation, we get:

Hence, the fugacity coefficient of a gaseous species is 1.25