Chapter 2

Question 1

What is a element?

Answer 1

Substance that can NOT be broken down into any other substance by chemical reaction

Question 2

What is a compound?

Answer 2

Substance consisting of two or more elements in a fixed ratio

Question 3

What are the four major elements?

Answer 3

Carbon, Hydrogen, Oxygen, and Nitrogen

Question 4

What are trace elements?

Answer 4

Elements required by an organism in minute quantities

Question 5

What is a atom?

Answer 5

Smallest unit of matter that still retains the properties of an element

Question 6

What is an isotope?

Answer 6

The same element that differ in number of neutrons

Question 7

What is potential energy?

Answer 7

Energy that matter has because of its location or structure

Question 8

What is a covalent bond?

Answer 8

Sharing of a pair of valence electrons by two atoms

Question 9

What is a molecule?

Answer 9

Two or more atoms held together by covalent bonds.

Question 10

What is a structual formula?

Answer 10

-notation used to represent atoms and bonding
–For example: H – H

Question 11

What is a molecular formula?

Answer 11

Abberivated formula: H₂

Question 12

What is a compound?

Answer 12

Two or more different elements?

Question 13

Define electronegativity?

Answer 13

Atom’s attraction for electrons in a covalent bond

Question 14

What is a nonpolar covalent bond?

Answer 14

Atoms share the electrons equally

Question 15

What is a polar covalent bond?

Answer 15

one atom is more electronegative, so atoms do NOT share the electrons equally

Question 16

What is an ionic bond?

Answer 16

A bond formed between cation and anion

Question 17

How do hydrogen bonds form?

Answer 17

When one hydrogen atom is covalently bonded to an electronegative atom is also attracted to another electronegative atom.

Question 18

What are Van der Waals interactions?

Answer 18

Weak attraction between molecules that are very close together as a result of charges.