The de Broglie wavelength of an electron with a velocity of 6.00 ...

[Tirant22]

The de Broglie wavelength of an electron with a velocity of 6.00  106 m/s is ________ m. The mass of the electron is 9.11  10-28 g.
 
  A) 8.25  109
  B) 8.25  1012
  C) 1.21  10-16
  D) 1.21  10-13
  E) 1.21  10-10

Question 2

When an atom loses an alpha particle,
 
  A) its atomic number decreases by 2 units and its mass number decreases by 4 units
  B) its atomic number increases by 1 unit but its mass number remains unchanged
  C) its mass number decreases by 1 unit but its atomic number remains unchanged
  D) neither its atomic number nor its mass number changes

[bblaney]

Answer to Question 1

E

Answer to Question 2

A