All of the following, except a _ might be studied by a microbiologist.

a)virus

b)bacteria

c)protozoan

d)human egg cell

Which best describes why nh4+ can form an ionic bond with cl-?

The drawing represents the movement of particles in a substance. what changes of state can this substance undergo

An atom of sodium-23 (atomic number = 11) has a positive charge of +1. give this information, how many electrons does it have? how many proteins and neutrons does this atom have