Answer:
answer is 12.18
Explanation:
(C2H5NH2, Kb = 5.6 x 10-4.)
Answer:
the Molar heat of Combustion of diphenylacetylene 
= 
Explanation:
Given that:
mass of diphenylacetylene = 0.5297 g
Molar Mass of diphenylacetylene = 178.21 g/mol
Then number of moles of diphenylacetylene = 
= 
= 0.002972 mol
By applying the law of calorimeter;
Heat liberated by 0.002972 mole of diphenylacetylene = Heat absorbed by 
+ Heat absorbed by the calorimeter
Heat liberated by 0.002972 mole of diphenylacetylene = msΔT + cΔT
= 1369 g × 4.184 J g⁻¹°C⁻¹ × (26.05 - 22.95)°C + 916.9 J/°C (26.05 - 22.95)°C
= 17756.48 J + 2842.39 J
= 20598.87 J
Heat liberated by 0.002972 mole of diphenylacetylene = 20598.87 J
Heat liberated by 1 mole of diphenylacetylene will be = 
= 6930979.139 J/mol
= 6930.98 kJ/mol
Since heat is liberated ; Then, the Molar heat of Combustion of diphenylacetylene =
Aqua regia is an oxidative mixture that is highly corrosive and is composed of hydrochloric acid and nitric acid. The Ea (rev) for the reaction is 3 kJ.
<h3>What is activation energy?</h3>
The activation energy is the minimum required energy by the reactant to undergo changes to form the product. The activation energy of the reverse reaction is given by the difference in the production state and transition state.
It is given as,
Ea (rev) = Ea (fwd) − ΔHrxn
Given,
ΔH° = 83KJ
Ea (fwd) = 86 kJ/mol
Substituting the values above as:
Ea (rev) = 86 - 83
= 3 kJ
Therefore, the activation energy of the reverse reaction is 3 kJ.
Learn more about activation energy, here:
brainly.com/question/14287952
#SPJ4
Answer: Option (b) is the correct answer.
Explanation:
State of a substance changes when heat is provided to a substance.
This is because when we heat water then intermoleclar forces present within its molecules tend to break down. Due to this molecules start to move away from each other.
As a result, kinetic energy of molecules increases and they collide rapidly. Hence, solid state of water changes into liquid state and upon excessive heating liquid state of water changes into vapor state.
Thus, we conclude that temperature of water needs to change in order to change its state of matter.
An isotope of nitrogen containing 7 neutrons would be nitrogen-7
