Answer : The change in enthalpy of the reaction is, -310 kJ
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 given main reaction is,

The intermediate balanced chemical reaction will be,
(1)

(2)

(3)

Now we will reverse the reaction 1 and multiply reaction 1 by 2, reaction 2 by 2 and reaction 3 by 3 then adding all the equations, we get :
(1)

(2)

(3)

The expression for enthalpy of formation of
will be,



Therefore, the change in enthalpy of the reaction is, -310 kJ
Answer:
The process of evaporative cooling helps the body is explained below in complete details.
Explanation:
Your body performs the application of the evaporative process when secreting. Sweat, which contains 90 percent water, commences evaporating. ... This appears in a cooling impression (described as evaporative cooling) that serves to sustain body temperature and cools the body down when it becomes too hot.
Answer:
320m
Explanation:
The vertical displacement is given by:

Assuming v₀=0, t=8:

Any lump of osmium is. Iridium and gold are also very close.
Answer:
(a) 1.2 rad/s
(b) 1.8 rad
Explanation:
Applying,
(a) α = (ω-ω')/t................ Equation 1
Where α = angular acceleration, ω = final angular velocity, ω' = initial angular velocity, t = time.
From the question,
Given: α = 0.40 rad/s², t = 3 seconds, ω' = 0 rad/s (from rest)
Substitute these values into equation 1
0.40 = (ω-0)/3
ω = 0.4×3
ω = 1.2 rad/s
(b) Using,
∅ = ω't+αt²/2.................. Equation 2
Where ∅ = angle turned.
Substitutting the values above into equation 2
∅ = (0×3)+(0.4×3²)/2
∅ = 1.8 rad.