This plateau is where a phase change occurs. Likely, this cooling curve observes the changing of a liquid into a solid (so that the temperature is quantifiable). As something cools, it’s losing energy to the surroundings; when a phase change occurs, like liquid to solid, energy isn’t lost directly from the atom, but instead the energy maintained by free motion of the atom is used. This lack of motion reduces it into a lattice (all while maintaining a constant internal energy), finalizing the phase change, after which energy is lost directly from the atom again.
Answer:
1)4×10^13Hz
2) 9.95×10-9J
Explanation:
From the image attached, it is clear that the work function of the palladium metal must first be obtained in joules. Then, the frequency is obtained from E=hf.
The kinetic energy if the photoelectrons is obtained as the difference between the energy of the photon and the work function of the metal.
At STP volume is 22.4 L
Molar mass NO₂ = 46.0 g/mol
1 mole ---------- 22.4 L
? mole ---------- 11.4 L
moles = 11.4 * 1 / 22.4
moles = 11.4 / 22.4
= 0.5089 moles of NO₂
Mass NO₂ :
moles NO₂ * molar mass
0.5089 * 46.0
= 23.4094 g of NO₂
hope this helps!
The correct answer is (1) one mole of NO2.
The gram formula mass is also known as the molar mass and is defined by the mass over one mole of a substance.
Hope this helps~
