Answer:
15.8 ft/s
Explanation:
= Velocity of car A = 9 ft/s
a = Distance car A travels = 21 ft
= Velocity of car B = 13 ft/s
b = Distance car B travels = ft
c = Distance between A and B after 4 seconds = √(a²+b²) = √(21²+28²) = √1225 ft
From Pythagoras theorem
a²+b² = c²
Now, differentiating with respect to time
∴ Rate at which distance between the cars is increasing three hours later is 15.8 ft/s
Answer:
H vaporization = 100.0788 kJ/mol
Explanation:
Use clausius clapyron's adaptation for the calculation of Hvap as:
Where,
P₂ and P₁ are the pressure at Temperature T₂ and T₁ respectively.
R is the gas constant.
T₂ = 823°C
T₁ = 633°C
The conversion of T( °C) to T(K) is shown below:
T(K) = T( °C) + 273.15
So, the temperature,
T₂ = (823 + 273.15) K = 1096.15 K
T₁ = (633 + 273.15) K = 906.15 K
P₂ = 400.0 torr , P₁ = 40.0 torr
R = 8.314 J/K.mol
Applying in the formula to calculate heat of vaporization as:
Solving for heat of vaporization, we get:
H vaporization = 100078.823 J/mol
Also, 1 J = 10⁻³ kJ
So,
<u>H vaporization = 100.0788 kJ/mol</u>