Answer:
A. -163.96kJ
B. -158.34kJ
Explanation:
Heat of combustion is the heat released when an element with oxygen at stp.
Reaction for the combustion of carbon:
C(s) + O2(g) --> CO2(g)
Enthalpy heat of combustion, C (using Hess law) = -393.5 kJ/mol
m = 5g
Molecular weight = 12 g/mol
No of moles = mass/molecular weight
= 5/12
= 0.417mol
DH = -393.5 * 0.417
= -163.96 kJ
B. Heat absorbed by the calorimeter = heat evolve by combustion
= mCH2ODT + mCcDT
Where CH2O is the specific heat capacity of the water in the calorimeter
Cc is the specific heat capacity of copper calorimeter
= (2500*4.184*14.1) + (2000*0.385*14.1)
= -158343J
= -158.34kJ
Answer: C. enzyme
Explanation:
A catalyst is a substance which increases the rate of a reaction by taking the reaction through a different path which involves lower activation energy and thus more molecules can cross the energy barrier and convert to products.
The catalyst itself does not take part in the chemical reaction and is regenerated as such at the end.
Enzymes are proteins that reduce the activation energy of biological reaction. Enzymes increase the speed of a reaction and help it to run faster. Thus they are also called as bio catalysts.
Activated complex is the transition state which is very unstable and is formed during the course when reactants are converted to products.
Explanation:
increases. because the num of electrons increass
