chemistry semester exam

In the measurement 0.503 L, which digit is the estimated digit? a. the 0 immediately to the left of the 3 b. 3 c. the 0 to the left of the decimal point d. 5

3

A magnesium atom loses 2 electrons. What is the net electrical charge? a. -2 b. +10 c. +2 d. 0

+2

What is the approximate energy of a photon having a frequency of 4 x 107 Hz? (h = 6.6 x 10 -34 J.s) a. 3 x 10 -26 J b. 3 x 10 -27 J c. 3 x 10 42 J d. 3 x 10 -41 J

3 x 10 -26 J

Express the product of 4.0 mc021-1.jpg 10mc021-2.jpg m and 8.1 mc021-3.jpg 10mc021-4.jpg m using the correct number of significant digits a. 3.2 x 10^1 b. 3 x 10^1 c. 3.24 x 10^1 d. 3.0 x 10^1

3.2 x 10^1

How many unpaired electrons are in a sulfur atom, which has the atomic number 16? a. 3 b. 1 c. 0 d. 2

2

Chlorine boils at 239 K. What is the bioling point of chlorine expressed in degrees C? a. 93 C b. 34 C c. -61 C d. -34 C

-34C

How many energy sublevels are in the second principal energy level? a. 4 b. 3 c. 2 d. 1

3

Which of the following mass units is the largest? a. 1 mg b. 1 dg c. 1 cg d. 1 ng

1 dg

The accepted value of a length measurement is 200 cm, and trhe experimental value is 198 cm. Calculate the % error. a. -2% b. 2% c. 1% d. -1%

1%

What is the volume of 80.0 g of ether if the density of ether is 0.70 g/mL? a. 5.6 g x 10 (1) b. 8.0 x 10 (1) c. 8.8 x 10 (-3) d. 1.1 x 10 (2)

1.1 x 10 (2)

What is the relative mass of an electron? a. 1/1840 the mass of a hydrogen atom b. 1/1840 the mass of an alpha particle c. 1/1840 the mass of a C-12 atom d. 1/1840 the mass of a neutron + proton

1/1840 the mass of a hydrogen atom

Which combination of subatomic particles would produce a positive ion? a. 10 protons and 11 electrons b. 10 electrons and 10 protons c. 10 protons and 9 electrons d. 10 protons and 9 neutrons

10 protons and 9 electrons

A conversion factor that shows the relationship between grams and kilograms is a. x100 b. (division sign)100 c. 1000g/ 1kg d. 1g/ 1000kg

1000g/ 1kg

Express the sum of 7.68 m and 5.0 m using the correct number of significant digits a. 12.7 m b. 10 m c. 13 m d. 12.68 m

12.7 m

How many unpaired electrons are in a sulfur atom, which has the atomic number 16? a. 1 b. 2 c. 3 d. 0

2

Which of the following electron configurations of outer sublevels is the most stable? a. 4d2 5s4 b. 4d5 5s1 c. 4d4 5s2 d. 4d3 5s3

4d2 5s4

What is the next atomic orbital in the series 1s, 2s, 2p, 3s, 3p? a. 2d b. 4s c. 3f d. 3d

4s

What is the maximum number of d orbitals in a principal energy level? a. 5 b. 3 c. 2 d. 1

5

How many protons, electrons, and neutrons does an atom with atomic number 50 and mass number 125 contain? a. 120 neutrons, 50 protons, 75 electrons b. 75 electrons, 50 protons, 50 neutrons c. 70 neutrons, 75 protons, 50 electrons d. 50 protons, 50 electrons, 75 neutrons

50 protons, 50 electrons, 75 neutrons

According to the Law of Conservation of Matter, how many grams of products can be expected if the total mass of the reactants is 50 grams? (assume no errors) a. 50g b. more than 50g c. about 10g d. half as much

50g

Using the periodic table, determine the number of neutrons in 16O. a. 24 b. 4 c. 8 d. 16

8

Which of the following represents a binary molecule (covalent) compound? a. PCl5 b. AgI c. BeHCO3 d. MgS

PCl5

What is one difference between a mixture and a compound? a. A compound can only be separated into its components by chemical means. b. A mixture can only be separated into its components by chemical means. c. A mixture must be uniform in composition. d. A compound consists of more than one phase.

A compound can only be separated into its components by chemical means.

Which discovery did J. J. Thomson make that improved upon Dalton's atomic theory? a. Atoms contain tiny, negatively charged electrons b. Atoms that combine do so in simple whole-number ratios c. Atoms are always in motion d. Atoms contain a tiny, positively charged nucleus

Atoms contain tiny, negatively charged electrons

Which of the following statements is true? a. Atoms of isotopes of an element have different numbers of neutrons. b. Atoms of isotopes of an element have different numbers of electrons. c. Atoms of isotopes of an element have different numbers of protons. d. Atoms of the same element all have the same mass.

Atoms of isotopes of an element have different numbers of neutrons.

Which of the following statements is true about ions? a. When an anion forms, more electrons are transferred to it b. Charges for ions are always written as numbers followed by a plus or minus sign c. Cations are common among nonmetals d. Anions are positively charged ions

Cations are common among nonmetals

Which of the following statements is true about ions? a. Anions form when an atom gains protons. b. Anions form when an atom loses protons. c. Cations form when an atom loses electrons. d. Cations form when an atom gains electrons.

Cations form when an atom loses electrons.

Which molecule has a single covalent bond? a. Cl(2) b. N(2) c. CO(2) d. CO

Cl(2)

In which of the following sets is the symbol of the element, the number of protons, and the number of electrons given correctly? a. In, 49 protons, 49 electrons b. F, 19 protons, 19 electrons c. Zn, 30 protons, 60 electrons d. Cs, 55 protons, 132.9 electrons

In, 49 protons, 49 electrons

What causes the shielding effect to remain constant across a period? a. Electrons are added to the same principal energy level b. The charge on the nucleus is constant c. Electrons are added to different principal energy levels d. The atomic radius increases

Electrons are added to the same principal energy level

Which model of the atom is thought to be true? a. Protons, electrons, and neutrons are evenly distributed throughout the volume of the atom b. The nucleus is made of protons, electrons, and neutrons c. The nucleus is made of electrons and protons d. Electrons are distributed around the nucleus and occupy almost all the volume of the atom

Electrons are distributed around the nucleus and occupy almost all the volume of the atom

A non polar covalent bond is found in a. HCl b. CaS c. H2O d. F2

F2

Which of the following represents a compound? a. H-3 b. H2O c. H d. O-16

H2O

Which of the following molecules is linear in shape? a. H2O b. HBr c. NH3 d. CCl4

HBr

How does atomic radius change from left to right across a period in the periodic table? a. It first increases, then decreases b. It tends to decrease c. It tends to increase d. It first decreases, then increases

It tends to decrease

The density of mercury is 5,427 kg/(m3). If the density of water is 1.0 g/mL, will mercury float or sink in water? a. Mercury will sink because the density of mercury is 5,427 g/mL, which is greater than the 1.0 g/mL density of water b. Mercury will sink because the density of mercury is 5.427 g/mL, which is greater than the 1.0 g/mL density of water c. Mercury will float because the density of mercury is 0.005427 g/mL, which is less than the 1.0 g/mL density of water d. Mercury will float because the density of mercury is 0.05427 g/mL, which is less than the 1.0 g/mL density of wate

Mercury will sink because the density of mercury is 5.427 g/mL, which is greater than the 1.0 g/mL density of water

The molecular formula for the compound hydrogen cyanide is HCN. What information does the molecular formula provide about hydrogen cyanide? a. The formula HCN shows that hydrogen cyanide could contain 2 atoms of each element; hydrogen, carbon and nitrogen, as long as there is a one to one ratio. b. The formula HCN shows that hydrogen cyanide has a single ionic bond between the hydrogen and carbon atoms and a triple ionic bond between the carbon and nitrogen atoms. c. The formula HCN indicates that a molecule of hydrogen cyanide contains one hydrogen atom, one carbon atom, and one nitrogen atom. d. The formula HCN shows that hydrogen cyanide has a single covalent bond between the hydrogen and carbon atoms and a triple covalent bond between the carbon and nitrogen atoms.

The formula HCN indicates that a molecule of hydrogen cyanide contains one hydrogen atom, one carbon atom, and one nitrogen atom

Which of the following is true about the electron configurations of the noble gases? a. The electrons with the highest energy are in an f sublevel. b. The electrons with the highest energy are in a d sublevel. c. The highest occupied s and p sublevels are partially filled. d. The highest occupied s and p sublevels are completely filled.

The highest occupied s and p sublevels are completely filled.

Which of the following is correct concerning subatomic particles? a. The electron was discovered by Goldstein in 1886. b. Cathode rays were found to be made of protons. c. The neutron was discovered by Chadwick in 1932. d. The proton was discovered by Thomson in 1880.

The neutron was discovered by Chadwick in 1932.

Which of the following statements correctly compares the relative size of an ion to its neutral atom? a. The radius of an anion is identical to the radius of its neutral atom. b. The radius of a cation is greater than the radius of its neutral atom. c. The radius of a cation is identical to the radius of its neutral atom. d. The radius of an anion is greater than the radius of its neutral atom.

The radius of an anion is greater than the radius of its neutral atom.

Identify an observation that is qualitative? a. room is 25 feet long b. a leaf is blowing in the wind c. how a piece of metal changes when heated d. the speed of a ball rolling downhill

a leaf is blowing in the wind

What is the charge of a cation? a. a positive charge b. The charge depends on the size of the nucleus. c. no charge d. a negative charge

a positive charge

When an electron moves from a lower to a higher energy level, the electron a. absorbs a continuously variable amount of energy. b. absorbs a quantum of energy. c. always doubles its energy. d. moves closer to the nucleus.

absorbs a quantum of energy

Which of the following processes involves a change in physical properties? a. rusting b. burning c. fermenting d. boiling

boiling

Which glassware will give the most accurate measurement of volume of liquids a. test tube b. graduated cylinder c. florence flask d. 5beaker

graduated cylinder

A substance that can be separated into two or more substances only by a chemical change is an a. compound b. mixture c. solution d. element

compound

If the spin of one electron in an orbital is clockwise, what is the spin of the other electron in that orbital? a. counterclockwise b. zero c. clockwise d. both clockwise and counterclockwise

counterclockwise

Atomic size generally a. decreases as you move from top to bottom within a group. b. increases as you move from left to right across a period. c. decreases as you move from left to right across a period. d. remains constant within a period.

decreases as you move from left to right across a period

Which of the following particles are free to drift in metals? a. electrons b. cations c. neutrons d. protons

electrons

What do chemical symbols and formulas represent, respectively? a. elements and compounds b. compounds and mixtures c. atoms and mixtures d. elements and ions

elements and compounds

The principal quantum number indicates what property of an electron? a. position b. speed c. electron cloud shape d. energy level

energy level

What is the element with the highest electronegativity value? a. fluorine b. calcium c. cesium d. helium

fluorine

Which state of matter expands when heated and is easy to compress? a. liquid only b. gas c. solid only

gas

Which state of matter takes both the shape and volume of its container? a. liquid only b. solid c. gas only

gas

Which of the following factors contributes to the decrease in ionization energy within a group in the periodic table as the atomic number increases? a. increase in size of the nucleus b. increase in atomic size c. increase in number of protons d. fewer electrons in the highest occupied energy level

increase in atomic size

Which of the following decreases with increasing atomic number in Group 2A? a. ionization energy b. shielding effect c. number of electrons d. ionic size

ionization energy

When a measurement is multiplied by a conversion factor, the numerical value a. and the actual size of the quantity measured remain the same b. is generally changed, but the actual size of the quantity measured remains the same c. remains the same, but the actual size of the quantity measured is generally changed d. and the actual size of the quantity measured are generally changed

is generally changed, but the actual size of the quantity measured remains the same

How does atomic radius change from top to bottom in a group in the periodic table? a. It first decreases, then increases. b. It tends to decrease. c. It tends to increase. d. It first increases, then decreases.

it tends to increase

Which temperature scale has no negative temperatures? a. Kelvin b. Celsius c. Joule d. Fahrenheit

kelvin

Which state of matter has a definite volume and takes the shape of its container? a. solid b. liquid only c. gas only

liquid only

What element in the second period has the largest atomic radius? a. potassium b. neon c. lithium d. carbon

lithium

The metals in Groups 1A, 2A, and 3A a. all form ions with a negative charge. b. lose electrons when they form ions. c. all have ions with a 1+ charge. d. gain electrons when they form ions.

lose electrons when they form ions

Which of the following pairs of elements is most likely to form an ionic compound? a. magnesium and fluorine b. oxygen and chlorine c. sodium and aluminum d. nitrogen and sulfur

magnesium and fluorine

An example of an extensive property of matter is a. pressure b. temperature c. mass d. hardness

mass

Who conducted experiments to determine the quantity of charge carried by an electron? a. Thomson b. Rutherford c. Millikan d. Dalton

milikan

All atoms are a. neutral, with the number of protons equaling the number of electrons. b. negatively charged, with the number of electrons exceeding the number of protons. c. positively charged, with the number of protons exceeding the number of electrons. d. neutral, with the number of protons equaling the number of electrons, which is equal to the number of neutrons.

neutral, with the number of protons equaling the number of electrons

What are the Group 1A and Group 7A elements examples of? a. nonmetallic elements b. representative elements c. transition elements d. noble gases

representative elements

Under what conditions can potassium bromide conduct electric? a. only when melted or dissolved in water b. only when it is in crystal form c. only when melted d. only when dissolved

only when melted or dissolved in water

Which of the following cannot be classified as a pure substance? a. orange juice b. oxygen gas c. silver metal d. gold

orange juice

A horizontal row of the periodic table is usually referred to as a a. period b. family c. property d. group

period

Three different people weigh a standard mass of 2.00 g on the same balance. Each person obtains a reading of 7.32 g for the mass of the standard. These results imply that the balance that was used is ____. a. accurate and precise b. precise c. accurate d. neither accurate nor precise

precise

Which of the following can be classified as a mixture? a. pure water b. pure air c. pure gold d. pure nitrogen

pure air

What types of atomic orbitals are in the third principal energy level? a. s and p only b. s, p, and d only c. p and d only d. s, p, d, and f

s, p, and d only

What element has the electron configuration 1s2 2S2 2P6 3S2 3P2? a. nitrogen b. selenium c. silver d. silicon

silicon

Which state of matter is characterized by having a definite shape and a definite volume? a. gas b. liquid only c. solid only

solid

What distinguishes a substance from a mixture? a. Substances are compounds, and mixtures are not b. Mixtures are groupings of elements, and compounds are not c. The composition of substances cannot vary, while the composition of mixtures can d. Samples of the same substance can have different intensive properties

substances are compounds, and mixtures are not

What is shown by the structural formula of a molecule or polyatomic ion? a. the number of ionic bonds b. the number of metallic bonds c. the shapes of molecular orbitals d. the arrangement of bonded atoms

the arrangement of bonded atoms

The octet rule states that, in chemical compounds, atoms tend to have a. more protons than electrons b. the electron configuration of a noble gas c. two electrons in their principal energy level d. more electrons than protons

the electron configuration of a noble gas

What does the number 84 in the name krypton-84 represent? a. the mass number b. twice the number of protons c. the atomic number d. the sum of the protons and electrons

the mass number

What information does a molecular formula provide? a. the simplest whole-number ratio of atoms that are bonded by the transfer of electrons b. information about a molecule's structure c. the number and kind of atoms that are bonded by the transfer of electrons d. the number and kind of atoms present in a molecule

the number and kind of atoms present in a molecule

The atomic emission spectra of a sodium atom on Earth and of a sodium atom in the sun would be a. the same as each other only in the ultraviolet range b. the same as those of several other elements c. different from each other d. the same

the same