The number of atoms of fluorine that are present in the molecules of CF4 is calculated as follows
1 x4 = 4 atoms of fluorine
in CF4 they are four atoms of fluorine since the subscribe 4 indicate that they are four atoms of fluorine
Molar mass of NaCl is 23 (Molar mass of sodium) + 35.5 (molar mass of chlorine) = 58.5
therefore 0.8 moles = 0.8 *58.5= 46.8g
Travelling along this pressure gradient, the gas expands and does work, and this removes energy from the gas. The cold temperature profile sneaks back towards the can, because the air is such a lousy conductor of heat, so the heat is all coming from the can.
Answer: 2.75×10^-7m
Explanation:
The work function refers to the smallest energy a photon must posses in order to cause the ejection of electrons from a metal surface.
If Eo= hfo
Eo=work function of the metal
fo=threshold frequency
h= Plank's constant
But Eo= hf= hc/wavelength
Wavelength= hc/Eo
We convert Eo to joules
4.50×1.6×10^-19=7.2×10^-19J
c=3×10^8ms-1
h=6.6×10^-34Js
Wavelength= 3×10^8×6.6×10^-34/7.2×10^-19
2.75×10^-7m