Except catalyst because catalyst typically speed up a reaction by reducing the activation energy or changing the reaction mechanism.
Answer:
Hydrogen
Explanation:
It is considered a special element due to its flexibility in giving up & taking in electrons, therefore making it good for organic & inorganic chemistry. Hydrogen has only one proton and one electron and is the only element which has no neutrons. it is considered as the simplest element in the universe and gives a valid reason for it to be the most abundant and common element in the universe.
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Answer:
The sum of the molar masses of each isotope of the element.
Answer:
a) 
b) 
d) 
d) 
Explanation:
From the question we are told that:
Moles of N2 
Atmospheric pressure 
Temperature 

Initial heat 
a)
Generally the equation for change in temperature is mathematically given by

Where




b)
Generally the equation for ideal gas is mathematically given by

For v double


Therefore



Total Work-done 



c)
Generally the equation for amount of heat added is mathematically given by



d)
Generally the equation for change in internal energy of the gas is mathematically given by


