Answer:
A. it is the lowest at low temperatures
Explanation:
It is true with respect to the kinetic energy of a molecule that the it is the lowest at low temperatures.
The kinetic energy of a molecule is the energy due to the motion of the particles within a substance.
- Kinetic energy is directly proportional to the temperature of a substance.
- The higher the temperature, the more the kinetic energy of the molecules within a system.
- At low temperature, kinetic energy is the lowest.
- At the highest temperature, kinetic energy is the highest
Answer:
Explanation:
<u>1) First law of thermodynamic (energy balance)</u>
- Heat released by the the hot water (345K ) = Heat absorbedby the cold water (298 K) + Heat absorbed by the calorimeter
<u>2) Energy change of each substance:</u>
Heat released or absorbed = mass × Specific heat × change in temperature
- density of water: you may take 0.997 g/ ml as an average density for the water.
- mass of water: mass = density × volume = 50.0 ml × 0.997 g/ml = 49.9 g
- Specif heat of water: 1 cal / g°C
- Heat released by the hot water:
Heat₁ = 49.9 g × 1 cal / g°C × (345 K - 317 K) = 49.9 g × 1 cal / g°C × (28K)
- Heat absorbed by the cold water:
Heat₂ = 49.9 g × 1 cal / g°C × (317 K - 298 K) = 49.9 g × 1 cal / g°C × (19K)
- Heat absorbed by the calorimeter
Heat₃ = Ccal × (317 K - 298 K) = Ccal × (19K)
<u>4) Balance</u>
49.9 g × 1 cal / g°C × (28 K) = 49.9 g × 1 cal / g°C × (19 K) + Ccal × (19 K)
Ccal = [49.9 g × 1 cal / g°C × (28 K) - 49.9 g × 1 cal / g°C × (19 K) ] / 19K
Ccal = 23.6 cal/ K
- Convert to cal / K to Joule / K
23.6 cal / K × 4.18 J / cal = 98.6 J/K
Which rounded to 2 signficant figures leads to 99 J/k, which is the first choice.
Answer:
Gases mix easily because of their high kinetic energy and low inter-molecular forces.
Explanation:
3CH4 refers to three molecules of a
compound and C3H12 refers to only one
molecule of a compound.
3CH4 and C3H12 are actually different
molecules though they contain the same
number and types of atoms. Recall that both
of them are hydrocarbons hence they
contain only hydrogen and carbon.
3CH4 refers to three molecules of methane
while C3H12 refers to one molecule of
diphenyl methane. Hence 3CH4 refers to
three molecules of a compound and C3H12
refers to only one molecule of a compound.
It's true because gravity retract everything.
