Chapter 2: Chemistry of Life Objects

Question 1

charge of protons

Answer 1

postive charge

Question 2

location of protons

Answer 2

in the central core of atom (atomic nucleus)

Question 3

charge of neutrons

Answer 3

no charge

Question 4

location of neutrons

Answer 4

in the atomic nucleus, slightly larger than protons

Question 5

charge of electrons

Answer 5

negatively charged

Question 6

location of electrons

Answer 6

outside atomic nucleus

Question 7

The bulk of an atom’s mass comes from its ___ and ___

Answer 7

protons and neutrons

Question 8

The first electron shell, which is closet to the nucleus, can hold __ electrons

Answer 8

2

Question 9

The second electron shell can hold __ electrons

Answer 9

8

Question 10

The third electron shell can hold ___ electrons (but is “satisfied” with only __)

Answer 10

18, 8

Question 11

Element

Answer 11

a substance that cannot be broken down into simpler substance by chemical means

Question 12

Atomic number

Answer 12

number of protons in the atomic nucleus; defines every element.

Question 13

Human body is made up of four major elements

Answer 13

hydrogen, oxygen, carbon, nitrogen

Question 14

Mass number

Answer 14

equal to sum all protons and neutrons in atomic nucleus

Question 15

Isotopes

Answer 15

atoms with the same atomic numbers but different mass number

Question 16

how isotopes are produced by changing the relative number of a specific subatomic particle

Answer 16

isotopes have the same atomic number but different mass numbers, which means the neutrons are changed.

Question 17

Atom

Answer 17

smallest unit of matter that retains original properies

Question 18

radioisotopes

Answer 18

unstable isotopes; high energy or radiation released by radioactive decay; allows isotope to assume more stable form

Question 19

three basic types of mixtures

Answer 19

suspensions, colloids, solutions

Question 20

Suspension

Answer 20

particles large and usually visible; settle out

Question 21

Colloid

Answer 21

two distinct components; particles small and not visible; do not settle out

Question 22

Solution

Answer 22

particles extremely small and not visible; do not settle out; one component dissolves in the other component

Question 23

Solute

Answer 23

substance dissolved

Question 24

Solvent

Answer 24

substance that dissolves solute

Question 25

Chemical bonds are formed when ___ of atoms interact.

Answer 25

valence electrons (outermost shell)

Question 26

Valence electrons determine how an atom interacts with other atoms; whether it will ____ with specific atom

Answer 26

form bonds

Question 27

Octet rule

Answer 27

atom is most stable when 8 electrons in valence electron.

Question 28

Duet rule

Answer 28

atoms with 5 or fewer electrons - atom is most stable when valence electron holds 2 electrons

Question 29

Ionic bond

Answer 29

electrons are transferred from metal atom to nonmetal atom

Question 30

2 formation of ions

Answer 30

cations and anions

Question 31

cation

Answer 31

positively charged ion; metal loses one or more electrons

Question 32

anion

Answer 32

negatively charged ion; nonmetal gains one or more electrons

Question 33

attraction between opposite charge bonds ions to one another forming ___

Answer 33

salt

Question 34

Covalent bonds

Answer 34

strongest bond; two or more nonmetals share electrons

Question 35

Two atoms can share one (___), two (____), three (____)

Answer 35

single bond, double bond, triple bond

Question 36

Nonpolar covalent bond

Answer 36

two non metals in molecule with similar or identical ectronegativities pull with equal force; share electrons equally

Question 37

Nonpolar molecules occur in 3 situations

Answer 37

atoms sharing electrons are same element
arrangement of atoms makes one atom unable to pull more strongly than another atom
bond is between carbon and hydrogen

Question 38

Nonpolar covalent bond- H2 (hydrogen molecule):

Answer 38

Electrons spend equal time around the two hydrogen atoms.

Question 39

Polar covalent bond

Answer 39

nonmetal with different electronegativites share electrons unequally; form polar molecules

Question 40

atom with ___ electronegativity becomes partially negative, pulls shared electrons close to itself

Answer 40

higher

Question 41

atom with ___ electronegativity becomes partially positive; shared electrons are pulled toward other atom

Answer 41

lower

Question 42

Dipoles

Answer 42

polar molecules with partially positive and partially negative ends

Question 43

polar covalent bond–H20 (water)

Answer 43

electrons spend more time around the more electronegative oxygen atom

Question 44

Hydrogen bonds

Answer 44

weak attractions between partially positive end of one dipole and partially negative end of another dipole

Question 45

Surface tension

Answer 45

responsible for key property of water

Question 46

____ water molecules are more strongly attracted to one another than to ____ air molecules at surface.

Answer 46

polar, nonpolar

Question 47

hydrogen bonds between water molecule create surface tension that causes ___

Answer 47

blood to form droplets