Study Guide: Exam 1 Ch. 2

Question 1

Which components of an atom do not add significantly to its mass?

Answer 1

The electrons in the atoms do not contribute significantly to the mass of it.

Question 2

The atomic number of an element is the same as the number of _______ in each atom.

Answer 2

protons

Question 3

Which elements are found in all living systems?

Answer 3

Carbon (C), hydrogen (H), nitrogen (N), oxygen (O), phosphorus (P), sulfur (S)

Question 4

A covalent bond is the sharing of _______ (neutrons/electrons/protons) between atoms, whereas an
ionic bond is the _______ (sharing/attraction/transfer) of electrons.

Answer 4

electrons, attraction

Question 5

What determines if a molecule is polar, nonpolar, or ionic?

Answer 5

The electronegativity between the atoms within the molecule determine its polarity or ionic charge.

Question 6

What property of water makes sweating a useful cooling device for humans?

Answer 6

The hydrogen bonds between water molecules contribute to its high heat capacity; this allows for the water to absorb the excessive heat from the skin.

Question 7

What is entropy? Can energy be created or destroyed?

Answer 7

Entropy is a measure of the disorder in a system. Energy can neither be created nor destroyed, it is converted from one form to another (not 100% efficiently however).

Question 8

What is the first law of thermodynamics?

Answer 8

Energy is neither created nor
destroyed.