The type of bond between atoms of potassium and chloride in a crystal of potassium chloride

a. hydrogen bond

b. ionic bond

c. polar covalent bond

d. pure covalent bond

e. metallic bond

It's an ionic bond because potassium is a metal and chlorine is a non-metal so the potassium donates an electron to the chlorine and so the potassium becomes a positive ion and the chlorine becomes a negative chloride ion. Opposite ion charges attract so an ionic lattice is formed.