Answer: -
C. The hydrogen at 10 °C has slower-moving molecules than the sample at 350 K.
Explanation: -
The kinetic energy of gas molecules increase with the increase in the temperature of the gas. With the increase in kinetic energy, the gas molecules also move faster. Thus with the increase of temperature, the speed of the molecules increase.
Temperature of first hydrogen gas sample is 10 °C.
10 °C means 273+10 = 283 K
Thus first sample temperature = 283 K
The second sample temperature of the hydrogen gas is 350 K.
Thus the temperature is increased.
So both the kinetic energy and speed of molecules is more for the hydrogen gas sample at 350 K.
Thus the hydrogen at 10 °C has slower-moving molecules than the sample at 350 K.
Hence the answer is C.
The number in isotope platinum-194 stands for the <em>total </em>amount of protons and neutrons. In other words, this is the mass. =)
Answer: -
A catalyst is a substance that speeds up the chemical reaction. In the first experiment it took 32 minutes for all the magnesium to react.
In the next it took 54 minutes for all the magnesium to react. So the reaction was slower the second time.
Thus a catalyst was not used.
Powdering up the Magnesium would mean increasing the surface area. More the surface area faster the reaction. Since the reaction is slowing down,
Magnesium was not powdered
If the temperature was decreased then kinetic energy would decrease of the reactant molecules and the reaction would slow down due to less number of collisions between reactant moleules.
So the temperature was decreased is a correct option.
Of the sodium nitrate as molarity of a solution is expressed as the number of moles of a given substance per 1000cm3 or 1dm3 of water
hope that helps
