1. Ideal gas particles:
A. have no mutual attraction and no individual volume.
B. have no mass or volume.
C. have no odor and no color.
D. have no density and do not form bonds.
Is it A?
2. Why does the density of gas in a hot air balloon decrease as the gas is heated?
A. The volume of gas decreases as temperature increases.
B. The mass of gas increases as temperature increases.
C. The mass of gas decreases as temperature increases.
D. The volume of gas increases as temperature increases.
Is it D?
3. During which stroke of a four-stroke internal combustion engine is the system's temperature raised because work is done to the gases?
A. Intake stroke
B. Power stroke
C. Compression stroke
D. Exhaust stroke
I have no idea
1 and 2 are right.
I'm not an internal combustion man but I think the answer is c. The compression stroke is when the piston is at the bottom of it's stroke and it has just pulled in the fuel, then it starts up and compresses the gas so that the gas occupies the smallest volume just before the firing takes place (the firing starts the power stroke) and work is done on the gas as it is compressed.
1. The answer is A. Ideal gas particles have no mutual attraction and no individual volume. To understand this, you can refer to the Kinetic Theory of Gases. According to this theory, ideal gas particles are assumed to be point masses without any volume or mutual attraction. In reality, gas particles do have a small volume and experience weak intermolecular forces, but these effects are negligible when considering ideal gases.
2. The correct answer is D. The volume of gas increases as temperature increases. To understand why, you can refer to the Ideal Gas Law, which states that the volume of a gas is directly proportional to its absolute temperature when pressure and amount of gas are constant. As the gas in a hot air balloon is heated, its temperature increases, causing the gas particles to move faster and collide with each other more frequently. These increased collisions result in an increase in the volume of the gas.
3. The answer is B. The Power stroke is the stroke during which the system's temperature is raised because work is done to the gases. In a four-stroke internal combustion engine, the power stroke is the stage where the ignited fuel-air mixture expands and exerts force on the piston, which in turn generates mechanical work. This rapid expansion of the gases leads to an increase in their temperature.
1. The correct answer is A. Ideal gas particles have no mutual attraction, meaning they do not exert attractive forces on each other, and no individual volume, meaning they are treated as point particles with no physical size.
2. The correct answer is D. The volume of gas increases as temperature increases. This is known as the ideal gas law, which states that as temperature increases, the average kinetic energy of the gas particles increases, causing them to move faster and occupy a larger volume.
3. The correct answer is C. During the compression stroke of a four-stroke internal combustion engine, the piston compresses the air-fuel mixture, which raises its temperature. This is because the compression work done on the gases increases their internal energy and thus their temperature.