How do you do these Chemistry questions?

Question

1. Account for the fact that alpha particles and beta particles are deflected in opposite directions by an electric field.

2. Predict the formula and the name of the compound formed by the following pairs of elements: (a) Ga and F (b) Li and H (c) Al and I (d) K and S

Answer 1

Alpha particles are basically He atoms without the electrons.  Consisting of 2 neutrons and 2 protons, it has a +2 charge, so it moves towards negatively charged electric fields.  However, Beta particles are free electrons that are given off by an atom; β particles are often negatively charged, so they move towards electric fields with a positive charge.

Gallium Fluoride - GaF4

Lithium hydride - LiH

Aluminum Iodide - AL i3 (AlI3)

Potassium sulfide - K2S