Question

Which of the following represent elements and which represent compounds? a. H b. He c. HF d. Hf

Answer 1

a. H - Element (H represents Hydrogen, which is a chemical element with atomic number 1.)

b. He - Element (He represents Helium, which is a chemical element with atomic number 2.)

c. HF - Compound (HF represents Hydrogen Fluoride, which is a chemical compound composed of hydrogen and fluorine atoms.)

d. Hf - Element (Hf represents Hafnium, which is a chemical element with atomic number 72.)