The four most common elements found in living organisms are

1.  ______ is an example of an element.

A) Water

B) Carbon

C) Glucose

D) Salt

2.  The four most common elements found in living organisms are ______.

A) nitrogen, oxygen, phosphorus, and carbon

B) carbon, oxygen, nitrogen, and hydrogen

C) carbon, oxygen, potassium, and calcium

D) oxygen, calcium, hydrogen, and carbon

3.   In order to have a positive charge, an atom must have ______.

A) more protons than electrons

B) more electrons than protons

C) more neutrons than protons

D) more protons than neutrons

4.   An atom’s _______ are found in its nucleus.

A) neutrons and protons

B) protons only

C) neutrons and electrons

D) electrons, protons, and neutron

5.  What is the difference between an ionic bond and a covalent bond?