Answer:
The approximate molar enthalpy of combustion of this substance is -66 kJ/mole.
Explanation:
First we have to calculate the heat gained by the calorimeter.

where,
q = Heat gained = ?
c = Specific heat = 
ΔT = The change in temperature = 3.08°C
Now put all the given values in the above formula, we get:


Now we have to calculate molar enthalpy of combustion of this substance :

where,
= enthalpy change = ?
q = heat gained = 8.2544kJ
n = number of moles methane = 

Therefore, the approximate molar enthalpy of combustion of this substance is -66 kJ/mole.
Answer:
1. active site
2. substrate.
3. activity
4. cofactor
5. complex
6. coenzyme.
Explanation:
1. A substrate binds to an enzyme at the active site where the reaction occurs.
2. In a catalyzed reaction, a reactant is often called a substrate.
3 activity is a measure of how fast an enzyme can convert the reagent to the product.
4. An inorganic substance necessary for the function of some enzymes is called a cofactor.
5. When properly aligned, the enzyme and substrate form an enzyme-substrate (ES) complex.
6. A small organic molecule necessary for the function of some enzymes is called a coenzyme.
Answer is: no reaction occurs.
No reaction occurs because magnesium (Mg) is less reactive than sodium (Na). Sodium is higher in activity series of metals and can not be reduced. <span> Metal X will replace another metal Y in a solution if X is higher in the activity series. </span>