It refers to a charged particle or atom. a. molecule
b. bromine
c. potassium
d. sulfur​

Explanation:

c. potassium

Hope it helps

It refers to a charged particle or atom.

A. molecule

B. bromine

C. potassium

D. sulfur

electron microscopy and scanning tunneling microscopes gives us a greater understanding of atoms by being able to see the atom itself, and lets us see some atomic reactions.

explanation:

he uptake of drugs from the intestine is often strongly influenced by diffusion. for example, consider a water-insoluble steroid for treating inflammation that is solubilized in aggregates of detergent molecules, called micelles. these micelles, aggregates of 80 soap molecules, have a molecular weight of 24,000, a diameter of 2.6 nm, and a charge of -27. the positively charge ions (counterions) in this system are na".