*Unit 2 Part 1: Bonds and pH

Question 1

_____ is made of matter.

Answer 1

Everything

Question 2

Chemical changes in _____ are essential to all life processes.

Answer 2

Matter

Question 3

The three states of matter are…

Answer 3

liquids, gases, solids.

Question 4

Elements are pure substances that cannot be _____.

Answer 4

broken down

Question 5

_____ percent of the mass of life is made of six elements.

Answer 5

96

Question 6

List the 6 elements that make up 96% of the mass of life.

Answer 6

Carbon, Oxygen, Phosphorus, Hydrogen, Nitrogen, Sulfur

Question 7

What is the mnemonic device that can be used to remember the 6 elements that make up the mass of life.

Answer 7

CHONPS

Question 8

What does CHONPS stand for?

Answer 8

Carbon, Oxygen, Phosphorus, Hydrogen, Nitrogen, Sulfur

Question 9

An _____ is the simplest particle of an element.

Answer 9

atom

Question 10

An atom is too small to see, so scientists use _____.

Answer 10

models

Question 11

Nucleus of an atom

Answer 11

Central core that contains protons and neutrons

Question 12

Protons

Answer 12

Positively charged

Question 13

Neutrons

Answer 13

No electic charge

Question 14

Electrons

Answer 14

Negatively charged

Question 15

Molecule

Answer 15

Two or more atoms held together by chemical bonds

Question 16

Bonds contain _____ energy that can be release or absorbed in chemical reactions.

Answer 16

chemical

Question 17

There are _____ types of bonds.

Answer 17

three

Question 18

List the types of bonds.

Answer 18

Covalent, Ionic, Hydrogen

Question 19

Covalent bonds form when…

Answer 19

2 atoms share electrons.

Question 20

Covalent bond are very _____ and very _____ bonds.

Answer 20

stable; strong

Question 21

Ion

Answer 21

Charged atom that has lost or gained an electron

Question 22

Cation

Answer 22

Ion that has lost electrons and has a positive charge

Question 23

Anion

Answer 23

Ion that has gained electrons and has a negative charge

Question 24

Ionic bonds form when…

Answer 24

oppositely charged ions are attracted to each other.

Question 25

Hydrogen Bonds

Answer 25

Attraction of weak charges between hydrogen and oxygen atoms

Question 26

pH measures...

Answer 26

the amount of H+ and OH- in a solution.

Question 27

The ph scale ranges from _____ to _____.

Answer 27

0; 14

Question 28

The pH of pure water is _____.

Answer 28

7

Question 29

A solution with a pH below 7 is _____.

Answer 29

acidic

Question 30

A solution with a pH above 7 is _____.

Answer 30

basic

Question 31

H+ means a solution has a pH that is _____.

Answer 31

acidic

Question 32

OH- means a solution has a pH that is _____.

Answer 32

basic

Question 33

Organisms can tolerate only small changes or proteins will begin to _____, so they maintain constant pH.

Answer 33

denature

Question 34

Buffers

Answer 34

Solutions that resist changes in pH

Question 35

Acids turn litmus paper _____, have a _____ taste, and have a pH _____ than 7.

Answer 35

red; sour; less

Question 36

Bases turn litmus paper _____, have a _____ taste, and have a pH _____ than 7.

Answer 36

blue; bitter; greater

Question 37

Is the following statement true or false? Acids feel slippery.

Answer 37

False

Question 38

Is the following statement true or false? Acids corrode metals.

Answer 38

True

Question 39

Is the following statement true or false? Bases feel slippery.

Answer 39

True

Question 40

Is the following statement true or false? Bases corrode metal.

Answer 40

False