CHEMISTRY REGENTS REVIEW ALL TOPICS

Question 1

which statement describes the earliest model of the atom

1) an atom is an invisible hard sphere

2) an atom has a small dense nucleus

3) electrons are negative particles in an atom

4) electrons in an atom have wavelike properties

Answer 1

1

Question 2

in all atoms of bismuth the number of electrons must equal the

number of protons

number of neutrons

sum of the number of neutrons and protons

difference between the number of neutrons and protons

Answer 2

1

Question 3

an orbital is a region in an atom where there is a high probabitlity of finding

an alpha particle

an electron

a neutron

a positron

Answer 3

2

Question 4

which electron shell in an atom of calcium in the ground state has an electron with the greatest amount of energy

1
2
3
4

Answer 4

4

Question 5

as the elements in period 2 are considered in order from lithium to flourine, there is an increase in the

atomic radius

electronegativity

number of electron shells

number of electrons in the fist shell

Answer 5

2

Question 6

which element is classified as a metalloid

boron

potassium

sulfur

xenon

Answer 6

boron

Question 7

strontium and barium have similar chemical properties because atoms of these elements have the same number of

protons
neutrons
electron shells
valance electrons

Answer 7

valance electrons

Question 8

which term represents the fixed proportion of elements in a compound

atomic mass
molar mass
chemical formula
density formula

Answer 8

chemical formula

Question 9

which two terms represent types of chemical formulas

mechanical and structural

mechanical and thermal

molecular and structural

molecular and thermal

Answer 9

3

Question 10

which element has metallic bonds at room temp

bromine

cesium

krypton

sulfur

Answer 10

cesium

Question 11

what is the number of electrons shared between the atoms in a molecule of nitrogen, N2

8
2
3
6

Answer 11

6

Question 12

given the equation representing a reaction
H + H yeilds H2
what occurs during this reaction?

a bond is broken and energy is absorbed

a bond is broken and energy is released

a bond is formed and energy is absorbed

a bond is formed and energy is released

Answer 12

4

Question 13

an atom of which element has the strongest attraction for electrons in a chemical bond

chlorine
carbon
phosphorus
sulfur

Answer 13

chlorine

Question 14

at STP, a 50 gram sample of H2O (l) and a 100 gram sample of H2O (l) have

the same chemical properties
the same volume
diff temperatures
diff empirical formulas

Answer 14

1

Question 15

what statement describes a mixture of sand and water at room temperature

it is heterogeneous and its components are in the same phase

it is heterogeneous and its componets are in different phases

it is homogenous and its componets are in the same phase

it is homogenous and its components are in different phases

Answer 15

2

Question 16

distillation is a process used to separate a mixture of liquids based on different

boiling points
densities
freezing points
solubilities

Answer 16

boiling points

Question 17

according to the kinetic molecular theory, which statement describes the particles in a sample of an ideal gas

the particles are constantly moving in circular patterns

the particles collide decreasing the total energy in the system

the particles have attractive forces between them

the particles are considered to have negligible volume

Answer 17

4

Question 18

for a chemical system at equilibrium the concentrations of both the reactants and the products must

decrease
increase
be constant
be equal

Answer 18

constant

Question 19

in terms of disorder and energy, systems in nature have a tendency to undergo changes toward

less disorder and lower energy

less disorder and higher energy

greater disorder and lower energy

greater disorder and higher energy

Answer 19

3

Question 20

the only two elements in alkenes and alkynes are

carbon and nitrogen

carbon and hydrogen

oxygen and nitrogen

oxygen and hydrogen

Answer 20

2

Question 21

which functional group contains a nitrogen atom and an oxygen atom

ester
ether
amide
amine

Answer 21

amide

Question 22

when a sample of Mg (s) reacts completely with O2(g), the Mg(s) loses 5 moles of electrons. How many moles of electrons are gained by the O2(g)

1 mol
2.5 mol
5 mol
10 mol

Answer 22

5 mol

Question 23

which statement describes the reactions in an electrochemical cell

oxidation occurs at the anode and reduction occurs at the cathode

oxidation occurs at the cathode and reduction occurs at the anode

oxidation and reduction both occur at the cathode

oxidation and reduction both occur at the anode

Answer 23

1

Question 24

what is the color of bromcresol green indicator in a solution with a pH value of 2

blue
green
red
yellow

Answer 24

4

Question 25

in which reaction is an atom of one element converted into an atom of another element combustion fermentation oxidation-reduction transmutation

Answer 25

4

Question 26

in which type of nuclear reaction do nuclei combine to form a nucleus with a greater mass alpha decay beta decay fusion fission

Answer 26

fusion

Question 27

which electron configuration represents the electrons in an atom of sulfur in an excited state 2-8-6 2-7-7 2-8-7 2-7-8

Answer 27

2

Question 28

which notations represent atoms that have the same number of protons but a different number of neutrons H-3 and He-3 S-32 and S-32 Cl-35 and Cl-37 Ga-70 and Ge-73

Answer 28

3

Question 29

what is the molarity of 2 liters of an aqueous solution that contains .5 mole of potassium iodide, KI 1 M 2 M .25 M .5 M

Answer 29

.25 M

Question 30

hydrochloric acid reacts faster with powdered zinc than with an equal mass of zinc strips because the greater surfact are of the powdered zinc decrease the frequency of particle collisions decreases the activation energy of the reaction increases the frequency of particle collisions increases the activation energy of the reaction

Answer 30

3

Question 31

which radioisotope requires long term storage as the method of disposal to protect living things from radiation exposure over time Pu-239 Fr-220 Fe-53 P-32

Answer 31

1

Question 32

state the number of protons in an atom of N-15

Answer 32

7

Question 33

state the number of electrons in each shell of an N-14 atom in the ground state

Answer 33

2-5

Question 34

based on the atomic mass of the element nitrogen on the periodic table compare the relative abundances of the naturally occuring isotopes of nitrogen

Answer 34

the relative abundances of the naturally occuring isotopes of N-14 is more abundant than N-15

Question 35

which statement describes a concept included in the wave mechanical model of the atom protons neutrons and electrons are located in the nucleus electrons orbit the nucleus in shells at fixed distances atoms are hard invisible spheres electrons are located in regions called orbitals

Answer 35

4

Question 36

as an electron in an atom moves from a higher energy state to a lower energy state, the atom becomes a negative ion becomes a poisive ion releases energy absorbes energy

Answer 36

3

Question 37

two atoms that are different isotopes of the same element have the same number of protons and the same number of neutrons the same number of protons but a different number of neutrons a different number of protons but the same number of neutrons a different number of protons and a different number of neutrons

Answer 37

2

Question 38

the element in group 14 period 3 of the periodic table is classified as a metal noble gas metalloid nonmetal

Answer 38

3

Question 39

which conclusion was developed as a result of the gold foil experiment atoms are mostly empty space all atoms are hard invisible spheres atoms have different volumes all atoms have the same volume

Answer 39

1

Question 40

which two particles each have a mass approximately equal to one atomic mass unit positron and proton positron and electron neutron and electron neutron and proton

Answer 40

4

Question 41

an excited potassium atom emits a specific amount of energy when one of its electrona moves from the first shell to the fourth shell the second shell to the fourth shell the fourth shell to the fifth shell the fourth shell to the second shell

Answer 41

4

Question 42

which list of elements includes a metal, a metalloid, and a noble gas? Rd, Cl, Ne Rn, Cl, Ne Sr, Si, Rn Si, Rb, Sr3

Answer 42

3

Question 43

which element has the lowest density at 298K and 101.3kPa argon fluorine nitrogen oxygen

Answer 43

3

Question 44

which statement describes the changes in bonding and energy that occur when a molecule of iodine forma two separate atoms of iodine a bond is formed as energy is absorbed a bond is formed as energy is released a bond is broken as energy is absorbed a bond is broken as energy is released

Answer 44

3

Question 45

the degree of polarity in the bond between a hydrogen atom and an oxygen atom in a molecule of water can be assessed using the difference in densities electronegativities melting points intermolecular forces

Answer 45

2

Question 46

which substance can not be broken down by a chemical change ammonia krypton ethanol water

Answer 46

2

Question 47

which term is used to express the concentration of an aqueous solution parts per million heat of fustion pressure at 0 degrees C volume at 0 degrees C

Answer 47

1

Question 48

which process represents a chemical change iodine sublimes water evaporates an ice cube melts a candle burns in air

Answer 48

4

Question 49

systems in nature tend to undergo changes toward higher energy and higher entropy higher energy and lower entropy lower energy and higher entropy lower energy and lower entropy

Answer 49

3

Question 50

which statement describes the bonding in an alkyne molecule there is at least one carbon to carbon double bond there is at least one carbon to carbon triple bond there is at least one carbon to oxygen single bond there is at least one carbon to oxygen double bond

Answer 50

2

Question 51

which term identifies a type of organic reaction deposition distillation polymerization vaporization

Answer 51

3

Question 52

in an electrochemical cell, oxidation occurs at the anode cathode salt bridge switch

Answer 52

anode

Question 53

which energy conversion occurs in an operating electrolytic cell chemical energy to electrical energy electrical energy to chemical energy nuclear energy to electrical energy electrical energy to nuclear energy

Answer 53

2

Question 54

one acid base theory states that a base is an H- donor H- acceptor H+ donor H+ acceptor

Answer 54

4

Question 55

the acidity or alkalinity of a solution can be measured by its pH value electronegativity value boiling point freexing point

Answer 55

1

Question 56

which nuclear emission has the greatest mass positron gamma ray beta particle alpha particle

Answer 56

4

Question 57

which statement describes the net change that occurs during nuclear fission electrons are converted to protons protons are converted to electrons mass is converted to energy energy is converted to mass

Answer 57

3

Question 58

which general trend is observed as the elements in period 2 are considered from left to right atomic mass decreases melting point increases electronegativity increases first ionization energy decreases

Answer 58

3

Question 59

one mole of bromine gas, Br2, has a mass of 35 g 70 g 79.9 g 159.8 g

Answer 59

4

Question 60

which sattement describes the charge and the radius of the magnesium ion formed when a magnesium atom loses two electrons the Mg ion is postive and has a radius larger than the Mg atom the Mg ion is negative and has a radius larger than the Mg atom the Mg ion is positive and has a radius smaller than the Mg atom the Mg ion is negative and has a radius smaller than the Mg atom

Answer 60

3

Question 61

the concept that matter is composed of tiny, discrete particles is generally attributed to the greeks romans english germans

Answer 61

greeks

Question 62

the first subatomic particle discovered was the proton neutron electron photon

Answer 62

electron

Question 63

According to the law of the conservation of mass, if the products of a reaction have a mass of 64 g, then the total mass of the reactants must be less than 64g must be equal to 64g must be more than 64g is not related to the mass of the products

Answer 63

2

Question 64

the gold foil experiment led scientists to conclude that an atoms positive charge is evenly distributed throughout its volume negative charge is mainly concentrated in its nucleus mass is evenly distributed throughout its volume volume is mainly unoccupied

Answer 64

4

Question 65

the model of the atom that pictured the atom with electrons stuch randomly throughout the mass of the atom was called the cannonball model plum pudding model planetary model wave mechanical model

Answer 65

2

Question 66

after bombarding a gold foil sheet with alpha particles scientists concluded that atoms mainly consist of electrons empty space protons neutrons

Answer 66

empty space

Question 67

experimental evidence indicates that the nucleus of an atom contains most of the mass of the atom contains a small percentage of the mass of the atom has no charge has a negative charge

Answer 67

1

Question 68

daltons atomic theory states that all atoms of an element are positively charged different elements can have the same mass atoms of a given element must be identical all the atoms in a compound are identical

Answer 68

3

Question 69

modern theory pictures an electron as a particle a wave only both a particle and a wave neither a particle nor a wave

Answer 69

3

Question 70

why did rutherford conclude that the atom was mostly empty space

Answer 70

most alpha particles went through it

Question 71

the atomic mass of an element is defined as the weighted average mass of that elements most abundant isotope least abundant isotope naturally occuring isotopes radioactive isotopes

Answer 71

3

Question 72

element x has two isotopes. if 72% of the element has an isotopic mass of 84.9 amu and 28% has an isotopic mass of 87 amu, the average atomic mass of element X is numerically equal to (72 + 98.9)(28 + 87) (72 - 84.9)(28 - 87) (.720)(84.9) + (.280)(87) (72)(84.9) + (28)(87)

Answer 72

3

Question 73

a neutral atom with 6 electrons and 8 neutrons is an isotope of carbon silicon nitrogen oxygen

Answer 73

1

Question 74

the major portion of an atoms mass consists of what

Answer 74

neutrons and protons

Question 75

a neutron has approximately the same mass as an alpha particle a beta particle an electron a proton

Answer 75

4

Question 76

what is the nuclear cahrge of an atom with a mass of 23 and an atomic number of 11 11 12 23 34

Answer 76

11

Question 77

compared to the charge and mass of a proton, an electron has the same charge and a smaller mass the same charge and the same mass an opposite charge and a smaller mass an opposite charge and the same mass

Answer 77

3

Question 78

which of the following statements are correct a proton is positively charged and a neutron is negatively charged a proton is negatively charged and a neutron is positively charged a proton is positively charged and an electron is negatively charged a proton is negatively charged and an electron is positively charged

Answer 78

3

Question 79

when electrons in an excited state fall to lower energy levels, energy is absorbed released neither absorbed nor released both absorbed and released

Answer 79

2

Question 80

the characteristic bright line spectrum of an atom is produced when nuclei undergo fission nuclei undergo fusion electrons move from higher to lower levels electrons move from lower to higher energy levels

Answer 80

3

Question 81

when the electrons of an excited atom fall back to lower energy levels, the emission of energy produces beta particles alpha particles spectral lines gamma radiation

Answer 81

3

Question 82

which atom in the ground state contains one completely filled p orbital Ne O He Be

Answer 82

1

Question 83

hat is the total number of electrons in the second principal energy level of a calcium atom in the ground state 6 2 8 18

Answer 83

8

Question 84

the atom of which element in the ground state has two unpaired electrons in the 2p sublevel Fl N Be C

Answer 84

C

Question 85

what is the toal number of occupied s orbitals in an atom of nickel in ground state 1 2 3 4

Answer 85

4

Question 86

which atom in hte ground state has only three electrons in the 3p sublevel phosphorus potassium argon aluminum

Answer 86

1

Question 87

what is the total number of occupied principal energy levels in a neutral atom of neon in the ground state 1 2 3 4

Answer 87

2

Question 88

in an atom of lithium in the ground state, what is the total number of orbitals that contain only one electron 1 2 3 4

Answer 88

1

Question 89

which of the following cannot be decomposed by chemical means sodium ethanol sucrose water

Answer 89

sodium

Question 90

a compound differs from an element in that a compound is homogenous has difinite composition has a definite melting point can be decomposed by a chemical reaction

Answer 90

4

Question 91

a compound differs from a mixture in that a compound always has a homogenous composition maximum of two elements minimum of three elements heterogenous composition

Answer 91

1

Question 92

a pure substance that is composed only of identical atoms is classified as a compound en elements a heterogeneous mixture a homogenous mixture

Answer 92

2

Question 93

most elements are metals nonmetals gases made in a laboratory

Answer 93

1

Question 94

which is a characteristic of all mixtures they are homogenous they are heterogeneous their compositions are in a definite ratio their compositions may vary

Answer 94

4

Question 95

a heterogeneous material may be an element a compound a pure substance a mixture

Answer 95

4

Question 96

which of these materials is a mixture water air methane magnesium

Answer 96

2

Question 97

each particle contained in hydrogen gas is made up of two identical hydrogen atoms chemically joined together. Hydrogen gas is a compound an element a homogenous mixture a heterogeneous mixture

Answer 97

an elements

Question 98

which of the following materials is a pure substance air water fire earth

Answer 98

2

Question 99

which statement is an identifying characteristic of a mixture a mixture can consist of a single element a mixture can be separated by physical means a mixture must have a definite composition by weight a mixture must be homogenous

Answer 99

2

Question 100

which substance can be decomposed by a chemical change ammonia aluminum magnesium manganese

Answer 100

ammonia

Question 101

a model of the atom that pictured the atom with electrons traveling in circular orbit was called the planetary model cannonball model wave mechanical model plum pudding model

Answer 101

1

Question 102

compared to the entire atom, the nucleus of the atom is smaller and contains most of the atoms mass smaller and contains little of the atoms mass large and contains most of the atoms mass large and contains little of the atoms mass

Answer 102

1

Question 103

neutral atoms must contain equal number of protons and electrons protons and neutrons protons, neutrons, and electrons neutrons and electrons

Answer 103

1

Question 104

compared with an electron a proton has more mass and the same charge more mass and an opposite charge equal mass and the same charge equal mass and an opposite charge

Answer 104

2

Question 105

the total number of electrons in a neutral atom of any element is always equal to the atoms mass number number of neutrons number of protons number of nucleons

Answer 105

3

Question 106

all isotopes of neutral atoms of sodium have 11 protons and 12 neutrons 12 protons and 11 neutrons 11 protons and 11 electrons 12 protons and 12 electrons

Answer 106

3

Question 107

an atom in the excited state contains more electrons than an atom in the ground state more protons than an atom in the ground state more potential energy than an atom in the ground state more mass than an atom in the ground state

Answer 107

3

Question 108

which of the following particles has the smallest mass neutron electron proton hydrogen atom

Answer 108

2

Question 109

a chemical formula is an expression used to represent mixtures only elements only compounds only elements and compounds

Answer 109

4

Question 110

which formula represents a compound Ca Cr CO Co

Answer 110

3

Question 111

What is the total number of atoms in the formula Ca(NO3)2 7 2 3 9

Answer 111

9

Question 112

pure nitrogen combines directly with an active metal to form a nitrate nitride nitrite permanganate

Answer 112

2

Question 113

Ag + Hsub2S yeilds Agsub2S +H sub what is the sum of the coefficients when teh equation is completely balanced using the smallest whole number coefficients 5 8 10 4

Answer 113

5

Question 114

pure oxygen reacts with metals to form oxalates oxalites oxides oxygenates

Answer 114

3

Question 115

which of the following is the formula of a compound Fr Mn LiH O3

Answer 115

3

Question 116

a chemical formula represents qualitative info only quantitative info only both quantitative and qualitative info neither info

Answer 116

3