Answer: 2.83 J/mol
Explanation:
Heat of solution, sometimes interchangeably called enthalpy of solution, is said to be the energy released or absorbed when the solute dissolves in the solvent. A solute is that which can dissolve in a solvent, to form a solution
Given
No of moles of CaCl = 7.5 mol
Total energy used = 21.2 J
Heat of solution = q/n where
q = total energy
n = number of moles
Heat of solution = 21.2 / 7.5
Heat of solution = 2.83 J/mol
Answer:
29.7 m/s fast, velocity is 29.7 m/s
Explanation:
Applying,
v² = u²+2gs...................... Equation 1
Where v = final velocity, u = initial velocity, g = acceleration due to gravity, s = distance.
Given: u = 0 m/s (dropped from height), s = 45 m
Constant: g = 9.8 m/s²
Substitute these values into equation 1
v² = 0²+2×9.8×45
v² = 882
v = √(882)
v = 29.7 m/s.
Hence the stone will be moving 29.7 m/s fast and the velocity is also 29.7 m/s
The first law, which deals with changes in the internal energy, thus becomes 0 = Q - W, so Q = W.
If the system does work, the energy comes from heat flowing into the system from the reservoir; if work is done on the system, heat flows out of the system to the reservoir
Answer: the golf ball with smooth surface would hit the ground first.
Jusitification:
An analysis of forces show two vertical forces acting on the golf balls.
1) one force is the weight (mg) which is vertical downward
2) the other force is the drag force exerted by the air on the golf balls, and it is vertical upward.
3) the drag force opposes the weight, so the acceleration downward is determined by the difference of the weiight and the drag force, until the balls reach the terminal speed (when the drag force equals the weight).
4) the drag force depends on the shape and area of the object falling. Being the surface of one ball smooth implies that the drag force will be less than the one on the other ball.
5) less drag force implies that the terminal velocity of the smooth ball will he higher, ant then it will hit the ground first.
