Answer : The standard enthalpy change for the combustion of CO(g) is, -283 kJ/mol
Explanation :
According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.
According to this law, the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation. That means the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.
The combustion of
will be,

The intermediate balanced chemical reaction will be,
(1)

(2)

Now we are reversing reaction 1 and then adding both the equations, we get :
(1)

(2)

The expression for enthalpy change for the reaction will be,



Therefore, the standard enthalpy change for the combustion of CO(g) is, -283 kJ/mol
Answer:
K₂Cr₂O₇(s) ⇒ 2 K⁺(aq) + Cr₂O₇²⁻(aq)
Explanation:
Potassium dichromate (K₂Cr₂O₇) is a strong electrolyte, that is, when dissolved in water (the medium), it dissociates in cation potassium (K⁺) and anion dichromate (Cr₂O₇²⁻). The balanced dissociation equation is:
K₂Cr₂O₇(s) ⇒ 2 K⁺(aq) + Cr₂O₇²⁻(aq)
Answer:
110L
Explanation:
Boyle's Law states that P1×V1=P2×V2
Volume is indirectly proportional to Pressure so P×V is constant
P1=55atm
V1=6L
P2=3atm
V2 is to be found
P1×V1=P2×V2
6×55=3×V2
330=3×V2
Answer: V2=110L