A laboratory vacuum pump can reduce the pressure in a chamber to ...

[joesmith1212]

A laboratory vacuum pump can reduce the pressure in a chamber to 1.0  10-7 Pa. If the volume of the chamber is 0.500 m3 and the temperature is 27C, how many molecules are left inside the chamber? (NA = 6.022  1023 molecules/mol, R = 8.
 
  31 J/mol  K) A) 1.2  1013
  B) 2.4  1013
  C) 1.2  1012
  D) 2.4  1012
  E) 1.2  1014

Question 2

An x-ray tube accelerates electrons through a potential difference of 50.0 kV. If an electron in the beam suddenly give up its energy in a collision,
 
  what is the shortest wavelength x-ray it could produce? (c = 3.00  108 m/s, h = 6.626  10-34 J  s, e = 1.60  10-19 C)

[welcom1000]

Answer to Question 1

A

Answer to Question 2

2.48  10-11 m

[joesmith1212]

Wow, this really help

[xiazhe]

Thanks for the timely response, appreciate it