Chapter 2 Test Review

Question 0

Elements of CHONPS?

Answer 0

Carbon, hydrogen, oxygen, nitrogen, phosphorus, sulfur

Question 1

4 elements that make up 96% of living matter

Answer 1

Carbon, hydrogen, oxygen, nitrogen

Question 2

Example of a trace element that all organisms need

Answer 2

Iron

Question 3

Example of a trace element that all vertebrates need

Answer 3

Iodine

Question 4

Mass number?

Answer 4

Protons+neutrons= mass number

Question 5

Atomic number?

Answer 5

Protons= electrons= atomic number

Question 6

How can two atoms be isotopes?

Answer 6

Isotopes are different forms of an element

Differ in neutrons and mass

Question 7

Number of electrons in first valence shell

Answer 7

2

Question 8

Number of electrons in second valence shell

Answer 8

8

Question 9

Number of electrons in third valence shell

Answer 9

18

Question 10

When is a covalent bond polar?

Answer 10

When one atom is more electronegative

The electrons are not shared equally

Question 11

Why are water molecules attracted to each other?

Answer 11

Hydrogen bonds attract water molecules to each other

Question 12

Remember

Answer 12

Elements are in their purest form

They cannot be broken down

Question 13

What makes up the nucleus of an atom?

Answer 13

Protons and neutrons

Question 14

Where are electrons?

Answer 14

Electron cloud/ shells

Question 15

Protons?

Answer 15

Positive
1 dalton
Determine element

Question 16

Neutrons?

Answer 16

Neutral
1 dalton
Determine isotope

Question 17

Electrons?

Answer 17

Negative
Weigh almost nothing
Determine chemical behavior

Question 18

Where is potential energy greater in an atom?

Answer 18

Farther from the nucleus

Question 19

Radioactive isotopes?

Answer 19

Nucleus decays spontaneously

Gives off particles and energy

Question 20

When are atoms unreactive?

Answer 20

They have a full valence shell

Question 21

What does chemical behavior of an atom depend on?

Answer 21

Number of electrons in the outermost shell

Question 22

Remember?(?)

Answer 22

Electrons in a shell have a characteristic energy level

Question 23

Orbitals?

Answer 23

Three-dimensional space with specific shapes (electron shells)

Question 24

When do chemical bonds form?

Answer 24

When atoms interact and complete their valence shells

Question 25

When do covalent bonds form?

Answer 25

Pairs of electrons are shared

Question 26

When is an ionic bond formed?

Answer 26

When electrons are transferred

Question 27

When is chemical equilibrium reached?

Answer 27

When forward and reverse reaction rates are equal

Concentration of reactants and products are equal

Question 28

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

Answer 28

Atom

Question 29

More electronegativity=

Answer 29

Stronger pull

Question 30

Remember!!!

Answer 30

In a chemical reaction, the reactants and products will never dis/appear

Atom in reactants are in products