multiple choice chemistry

which of the following is an intensive property of matter?

density

a volume of 1 millliter is equivalent to

1 cubic centimeter.

0.25 g is equivalent to

250 mg

0.05 cm is the same as

0.5 mm

A measurement that closely agrees with an accepted value is best described as

accurate

A numerical result is said to have good precision if

repeated measurements agree closely

The measurement 0.035550 g rounded off to two significant figures would be

0.036 g

The number of significant figures in the measurement 0.000 305 kg is

three significant figures.

1.06 L of water is equivalent to

1060 mL

An atom is electrically neutral because

the number of protons equals the number of electrons.

The average atomic mass of an element is the average of the atomic masses of its

naturally occuring isotopes

The atomic number of neon is 10. The atomic number of calcium is 20. Compared with a mole of neon, a mole of calcium contains

an equal number of atoms

Which of the following is the symbol for an alpha particle?

4 over 2 He

In nuclear reactors, the role of control rods is to

absorb neutrons

In a chemical reaction

the mass of the reactants equals the mass of the products

Which observation does not indicate that a chemical reaction has occured?

change in total mass of substances

In the word equation, sodium oxide + water —> sodium hydroxide, the formula for sodium hydroxide is represented by

NaOH

When the equation Fe3O4 + Al —> Al2O3 + Fe is correctly balanced, what is the coefficient of Fe?

9

Which equation is not balanced

2H2 + O2 —> H20

An element in the activity series can replace any element

below it on the list

What is the balanced equation when aluminum reacts with copper (II) sulfate?

2AL + 3CUSO4 —> AL2 (S04)3 + 3 CU

Which reaction does not occur?

2HF + CL2 —> F2 + 2HCL

A mutual electrical attraction between the nuclei and valence electrons of different atoms that binds the atoms together is called a

chemical bond

The electrons involved in the formation of a chemical bond are called

valence electrons

If two covalently bonded atoms are identical the bond is

nonpolar covalent

If the atoms that share electrons have an unequal attraction for the electrons the bond is called

polar covalent

What are shared in a covalent bond?

electrons

The B—F bond in BF3 (electronegativity for B is 2.0; electronegativity for F is 4.0) is

ionic

A formula that shows only the types and numbers of atoms combined in a single molecule is called a

molecular formula.

In a crystal, the electrons of adjacent ions

attract each other

The equal but opposite charges present in the two regions of a polar molecule create a

dipole

The following molecules contain polar bonds. The only polar molecule is

NH3

The major difference between a 1s orbital and a 2s is that

the 2s orbital is at a higher energy level

The p orbitals are shaped like

dumbbells

The number of orbitals for the d sublevel is

5

The total number of orbitals that can exist at the second main energy level is

4

If n is the principal quantum number of a main energy level, the number of electrons in that energy level is

2n².

The statement that an electron occupies the lowest available energy orbital is

the Aufbau principle.

“Orbitals of equal energy are each occupied by one electron before any is occupied by a second electron, and all electrons in singly occupied orbitals must have the same spin” is a statement of

the Hund's rule.

The Aufbau principle states that an electron

occupies the lowest available energy level

The person whose work led to a periodic table based on increasing atomic number was

Moseley

The elements in Group 1 on the periodic table are known as the

alkali metals

A measure of the ability of an atom in a chemical compound to attract electrons from another atom in the compound is called

electronegativity

What is removed when the ionization energy is supplied to an atom of an element?

an electron

In a row in the periodic table, as the atomic number increases, the atomic radius generally

decreases

As you move down Group 14 in the periodic table from carbon through lead, atomic radii

generally increase

Valence electrons are those s and p electrons

in the highest energy level

The number of valence electrons in Group 17 elements is

7

Carbon-dioxide dissolved in water is an example of which solute-solvent combination

gas-liquid

Raising the collision rate between solute and solvent

increases the rate of dissolution

Pressure has the greatest effect on the solubility of

gases in liquids

Sugar dissolved in water in an example of which solute-solvent combination?

solid-liquid

Substances whose water solutions conduct electricity easily

ionize in water

Which of the following does NOT increase the rate of dissolving a solid in water

using larger pieces of solid

A solute crystal is dropped into a solution containing dissolved solute. It falls to the bottom of the beaker and does not dissolve after vigorous stirring. What does this indicate about the solution?

It is probably saturated.

Which of the following is likely to produce crystals if disturbed?

a supersaturated solution

Unlike in an ideal gas, in a real gas

the particles exert attractive forces on each other

What determines the average kinetic energy of the molecules of any gas?

temperature

Which is an example of effusion?

air slowly escaping from a pinhole in a tire

Under which conditions do real gases resemble ideal gases?

low pressure and high temperature

Why does the air pressure inside the tires of a car increase when the car is driven?

The air particles inside the tire increase their speed because their temperature rises

Equal volumes of diatomic gases under the same condition of temperature and pressure contain the same number of

molecules

If gas A has a molar mass greater than that of gas B and samples of each gas at identical temperatures and pressures contain equal number of molecules, then

the volume of gas A and B are equal

Standard temperature is exactly

0 degrees celsius

According to the kinetic-molecular theory, gases condense into liquids because of

forces between molecules

The compressibility of a liquid is generally

less than that of a gas

The intermolecular forces between particles are

stronger in liquids than in gases

What is vaporization?

the process by which a liquid changes to a gas

Which of the following causes particles in a liquid to escape into a gas state?

high kinetic energy

The compressibility of solids is generally

lower than the compressibility of liquids and gases

In general, most substances are

most dense in the solid state

The difference between crystalline and amorphous solids is determined by

amount of order in particle arrangement

Which type of crystal consists of positive metal cations surrounded by valence electrons that are donated by the metal atoms and belong to the crystal as a whole?

Metallic

Molecules at the surface of a liquid can enter the vapor phase only if

their energy is high enough to overcome the attractive forces in the liquid

At its triple point, water can

exist in equilibrium in three different phases

Above the critical temperature, a substance

cannot exist in the liquid state

At a given temperature, different liquids will have different equilibrium vapor pressures because

the attractive forces between the particles differ among liquids

A volatile liquid

evaporates readily

Why doesn’t water in lakes and ponds of temperate climates freeze solid during the winter and kill nearly all the living things it contains?

Ice floats