Answer:
thermal energy, mechanical energy and chemical energy.
Explanation:
Our body goes into catabolism during running. Complex stored food molecules are broken down into simpler molecules that enter the blood stream and provide energy or fuel for running.
Mechanical energy is the sum of the kinetic and potential. During running we move our limbs, set our body in motion and cover a certain distance. Thus we utilize mechanical energy.
Thermal energy is characterized by a change in temperature. When running there is an increasing in body temperature which is manifested as sweat from the body.
thermal, mechanical, and chemical.
b. A 100.0 g sample of liquid ethanol vaporizes at its boiling point. Hvap = 38.6 kJ/mol
The heat required for the following two processes are:
a. 10.74 KJ
b. 83.92 KJ
Part a)
Given:
Mass (m) of ethanol = 100g
Heat of fusion, Hfus = 4.94 kJ/mol
To find:
Heat (Q) =?
Mass of C₂H₅OH = 100g
Molar mass of C₂H₅OH = (2x12)+ (5x1) + 16 + 1 = 46g/mol
Number of Mole = Mass /Molar Mass
Number of mole (n) of C₂H₅OH = 100/46 = 2.174 moles.
Calculation for Heat of fusion:
Q = n x Hfus
Q = 2.174 mol x 4.94 kJ/mol
Q = 10.74KJ
Therefore, 10.74 KJ of heat is required to melt the ethanol.
Part b)
Given:
Mass of C₂H₅OH = 100g
Heat of vaporization, Hvap = 38.6 kJ/mol
To find:
Heat (Q) =?
Calculation for Heat of vaporization:
As calculated above, the number of mole in 100g of ethanol, C₂H₅OH is 2.174 moles.
The heat required to vaporize the ethanol can be obtained as follow:
Q = n x Hvap
Q = 2.174 mol x 38.6 kJ/mol
Q = 83.92 KJ
Therefore, 83.92 KJ of heat is required to vaporize the ethanol.
Find more information about Heat of fusion here:
Answer:
A. 10.74 KJ
B. 83.92 KJ
Explanation:
A. Data obtained from the question include the following:
Mass (m) of ethanol = 100g
Heat of fusion, Hfus = 4.94 kJ/mol
Heat (Q) =..?
Next, we shall determine the number of mole in 100g of ethanol, C2H5OH. This is illustrated below:
Mass of C2H5OH = 100g
Molar mass of C2H5OH = (2x12)+ (5x1) + 16 + 1 = 46g/mol
Number of mole (n) of C2H5OH =..?
Mole = Mass /Molar Mass
Number of mole (n) of C2H5OH = 100/46 = 2.174 moles.
Now, we can obtain the heat required to melt the ethanol as follow:
Q = n x Hfus
Q = 2.174 mol x 4.94 kJ/mol
Q = 10.74KJ
Therefore, 10.74 KJ of heat is required to melt the ethanol.
B. Data obtained from the question include the following:
Mass of C2H5OH = 100g
Heat of vaporisation, Hvap = 38.6 kJ/mol
Heat (Q) =..?
As calculated above, the number of mole in 100g of ethanol, C2H5OH is 2.174 moles.
The heat required to vaporise the ethanol can be obtained as follow:
Q = n x Hvap
Q = 2.174 mol x 38.6 kJ/mol
Q = 83.92 KJ
Therefore, 83.92 KJ of heat is required to vaporise the ethanol.
C. From the above calculations, a higher amount of heat energy i.e 83.92 KJ is required to vaporise the ethanol and a lesser amount of heat energy i.e 10.74 KJ is needed to melt the ethanol.
it really easy its true
(Assume the balloon stretched very easily and the temperature was constant.)
Answer:
P₂ = 0.8 atm
Explanation:
Given data:
Initial pressure = 1 atm
Initial volume = 7 L
Final volume = 9 L
Final pressure = ?
Solution:
P₁V₁ = P₂V₂
P₁ = Initial pressure
V₁ = Initial volume
P₂ = Final pressure
V₂ = Final volume
Now we will put the vales in formula.
P₁V₁ = P₂V₂
P₂ = P₁V₁ /V₂
P₂ = 1 atm × 7 L / 9 L
P₂ = 7 atm. L / 9 L
P₂ = 0.8 atm