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.
30ml of a 2.50 M hydrochloric acid solution is required to make 100.0 mL of a 0.750 M solution.
<h3>What is HCl?</h3>
HCl is an acid which is made up of hydrogen and chlorine gas.
By the formula of dilution
M1V1 = M2V2
where V1 = 2.50 m
M2 = 100.0
V2 = 0.750 m
M1 × 2.50 m = 100.0 × 0.750 m
M1 = 30 ml
Thus, the M1 is 30 ml option a is correct.
Learn more about HCl
brainly.com/question/3637432
Note the signs of equilibrium:-
- Reaction don't procede forward or backward
- Concentration of products and reactants remains same .
So
if
Concentration of A is 2M then concentration of B should be same .
So equilibrium constant K is 1
![\\ \rm\rightarrowtail K=\dfrac{[Products]^a}{[Reactants]^b}](https://tex.z-dn.net/?f=%5C%5C%20%5Crm%5Crightarrowtail%20K%3D%5Cdfrac%7B%5BProducts%5D%5Ea%7D%7B%5BReactants%5D%5Eb%7D)
So
