How many atoms are in 7.2 MOL of Chlorine?

Which statement describes james chadwick’s discovery.

What shape would a molecule with two bound groups and two lone pairs have?

Use the de broglie's wave equation to find the wavelength of an electron moving at 7.3 × 106 m/s. show your work. note: h = plank's constant (6.62607 x 10-34 j s)