Exams 1-3 review

Question 1

true or false: nonmetals tend to lose electrons

Answer 1

false

Question 2

true or false: experiments are needed to validate a theory

Answer 2

true

Question 3

true or false: once a theory is proposed, it is considered fact

Answer 3

false

Question 4

true or false: an observation explains why nature does something

Answer 4

false

Question 5

true or false: a scientific law summarizes a series of related observations

Answer 5

true

Question 6

true or false: in both solids and liquids, the atoms or molecules pack closely to one another

Answer 6

true

Question 7

true or false: liquids are highly compressible

Answer 7

false

Question 8

true or false: protons and electrons have opposite but equal in magnitude charges

Answer 8

true

Question 9

true or false: alkali metals are generally not reactive

Answer 9

false

Question 10

a substance that cannot be chemically broken down into simpler substances is

Answer 10

an element

Question 11

a substance composed of 2+ elements in a fixed, definite proportion is a

Answer 11

compound

Question 12

isotopes of the same element differ only in number of :

Answer 12

neutrons

Question 13

physical or chemical change?
sugar heated to caramel

Answer 13

C

Question 14

physical or chemical change?
water cooled to ice

Answer 14

P

Question 15

physical or chemical change?
baking soda dissolved in water

Answer 15

P

Question 16

how many SF in 0.9810

Answer 16

4

Question 17

a covalent bond is best described as:

Answer 17

a pair of electrons holding neighboring nuclei at a fixed distance

Question 18

name HF

Answer 18

hydrofluoric acid

Question 19

name CaS

Answer 19

calcium sulfide

Question 20

name Ni2(SO4)3

Answer 20

nickel (III) sulfate

Question 21

name HClO3

Answer 21

chloric acid

Question 22

name P4O10

Answer 22

tetraphosphourous decoxide

Question 23

formula for sulfurous acid:

Answer 23

H2SO3

Question 24

define a limiting reagent

Answer 24

the reagent that runs out first and determines how much product is made

Question 25

how can you tell if a reaction is an oxidation-reduction reaction?

Answer 25

check oxidation states; changing oxidation states indicates transfer of E-

Question 26

as volume increases, pressure

Answer 26

decreases

Question 27

as temperature increases, pressure

Answer 27

increases

Question 28

what is the maximum # of D orbitals in any energy level?

Answer 28

5

Question 29

if N=2, what can L be?

Answer 29

0, 1

Question 30

Where does energy absorbed during an endothermic reaction go?

Answer 30

this energy raises the potential energy of the bonds formed in the products thereby “storing” that energy

Question 31

Why do atoms emit only certain wavelengths of light when they are excited? (why do line spectra exist)?

Answer 31

electrons can occupy only certain energy levels (n=1,2…) and nothing in between, which means that they transition between those energy levels, the exact and corresponding energy is emitted as photons, with no energies in between

Question 32

Which noble gas has the highest ionization energy? explain

Answer 32

He because it is smallest and most difficult to remove the highest energy valence electron