Chem midterm review

Dalton incorporated the law of conservation of mass into his atomic theory by asserting that

atoms are indivisible

In oxides of nitrogen, such as N₂O, NO, NO₂, and N₂O₃, atoms combine in small whole-number ratios. This evidence supports the law of

multiple proportions

According to the law of conservation of mass, when sodium, hydrogen, and oxygen react to form a compound, the mass of the compound is _______ the sum of the masses of the individual elements

equal to

The principles of the atomic theory recognized today were conceived by

Dalton

According to Dalton's atomic theory, atoms

of each element are identical in size, mass, and other properties

True or false: atoms of the same element may have different masses?

True

Experiments with cathode rays led to the discovery of the

electron

Whose series of experiments identified the nucleus of the atom?

Rutherford

Because most particles fired at metal foil passed straight through, Rutherford concluded that

atoms were mostly empty space

A positively charged particle with mass 1.673 x 10⁻²⁴ g is a

proton

A nuclear particle that has about the same mass as a proton but with no electrical charge is called a

neutron

True or false: The nucleus of an atom contains nearly all of the atom's volume

false

True or false: The nucleus of an atom is positively charged

true

True or false: The nucleus of an atom contains nearly all of the atom's mass

true

True or false: The nucleus of an atom is very dense

true

Which part of an atom has a mass approximately equal to 1/2000 of the mass of a common hydrogen atom?

electron

Protons within the nucleus are attracted to each other by

the nuclear force

An atom is electrically neutral because

the numbers of protons and electrons are equal

Most of the volume of an atom is occupied by the

electrons

The smallest unit of an element that can exist either alone or in combination with other such particles of the same or different elements is the

atom

The radius of an atom extends to the outer edge of the

region occupied by the electrons

Isotopes are atoms of the same element that have different

masses

The atomic number of oxygen, 8, indicates that there are 8

protons in the nucleus of an oxygen atom

As the atomic number increases, the number of electrons in a neutral atom

increases

All atoms of the same element have the same

atomic number

The relative atomic mass of an atom can be found by comparing the mass of the atom to the mass of

one atom of carbon-12

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

naturally occurring isotopes

An aluminum isotope consists of 13 protons, 13 electrons, and 14 neutrons. Its mass number is

27

Neon-22 contains 12 neutrons. It also contains

10 protons and 10 electrons

Avogadro's number is

the number of particles in 1 mole of a pure substance

The mass of 1 mole of chromium (atomic mass 51.996 amu) is

51.996 g

How many moles of atoms are in 50.15 g of mercury (atomic mass 200.59)?

0.2500 mol

A prospector finds 39.39 g of pure gold (atomic mass 196.9665 amu). How many atoms is this?

1.204 x 10²³ atoms

A sample of tin (atomic mass 118.71 amu) contains 3.01 x 10²³ atoms. The mass of the sample is

59.3 g

The frequency of electromagnetic radiation is measured in waves/second, or

hertz

According to the particle model of light, certain kinds of light cannot eject electrons from metals because

The energy of the light is too low

If electromagnetic radiation A has a lower frequency than electromagnetic radiation B, then compared to B, the wavelength of A is

longer

The distance between two successive peaks on adjacent waves is its

wavelength

Max Planck proposed that a hot object radiated energy in small, specific amounts called

quanta

The energy of a photon is related to its

frequency

The emission of electrons from metals that have absorbed photons is called the

photoelectric effect

A line spectrum is produced when an electron moves from one energy level

to a lower energy level

When the pink-colored light of glowing hydrogen gas passes through a prismn, it is possible to see

four lines of different colors

The Bohr model of the atom was an attempt to explain hydrogen's

line-emission spectrum

For an electron in an atom to change from the ground state to an excited state,

energy must be absorbed

If electrons in an atom have the lowest possible energies, the atom is in the

ground state

According to the Bohr model of the atom, the single electron of a hydrogen atom circles the nucleus

in specific, allowed orbits

True or false: The Heisenberg uncertainty principle states that it is impossible to determine simultaneously both the position and velocity of an electron or any other particle

True

True or false: The Heisenberg uncertainty principle is one of the fundamental principles of our present understanding of light and matter

True

True or false: The Heisenberg uncertainty principle helped lay the foundation for the modern quantum theory

True

True or false: The Heisenberg uncertainty principle helps to locate an electron in an atom

False

A three dimensional region around a nucleus where an electron may be found is called a(n)

orbital

True or false: According to the quantum theory of an atom, in an orbital an electron's position cannot be known precisely

True

True or false: According to the quantum theory of an atom, in an orbital an electron has no energy

False

True or false: According to the quantum theory of an atom, in an orbital electrons cannot be found

False

True or false: According to the quantum theory of an atom, in an orbital electrons travel around the nucleus on paths of specific radii

False

The quantum number that indicates the position of an orbital about the three axes in space is the

magnetic quantum number

How many quantum numbers are neeed to describe the energy state of an electron in an atom?

4

The main energy levels of an atom are indicated by the

principal quantum number

The angular momentum quantum number indicates the

shape of an orbital

The spin quantum number of an electron can be thought of as describing

the direction of electron spin

An electron for which n = 4 has more ______ than an electron for which n = 2

energy

The set of orbitals that are dumbbell shaped and directed along the x, y, and z axes are called

p orbitals

The number of orbitals for the d sublevel is

5

For the f sublevel, the number of orbitals is

7

How many orientations can an s orbital have about the nucleus?

1

True or false: Two electrons can occupy the s orbitals at each energy level as long as they have opposite spins

True

True or false: Two electrons can occupy the s orbitals at each energy level as long as they have the same spin

False

True or false: No more than 8 electrons can occupy the s orbitals at each energy level

False

True or false: One electron can occupy the s orbitals at each energy level

False

How many electrons are needed to completely fill the fourth energy level?

32

If the third main energy level contains 15 electrons, how many more could it possibly hold?

3

The main energy level that can hold only two electrons is the

first

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

the Aufbau principle

The statement that no two electrons in the same atom can have the same four quantum numbers is

the Pauli exclusion principle

What rule requires that each of the p orbitals at a particular energy level receive one electron before any of them can have two electrons?

Hund's rule

The atomic sublevel with the next highest energy after 4p is

5s

If the s and p sublevels of the highest main energy level of an atom are filled, how many electrons are in this main energy level?

8

An element with 8 electrons in its highest main energy level is a

noble gas

The idea of arranging the elements in the periodic table according to their chemical and physical properties is attributed to

Mendeleev

Mendeleev left spaces in his periodic table and predicted the existence of three elements and their

properties

Mendeleev noticed that properties of elements usually repeated at regular intervals when the elements were arranged in order of increasing

atomic mass

Mendeleev predicted that the spaces in his periodic table represented

undiscovered elements

Moseley's work led to the realization that elements with similar properties occured at regular intervals when the elements were arranged in order of increasing

atomic number

The discovery of what elements added a new column to Mendeleev's periodic table?

noble gases

What are the radioactive elements with atomic numbers from 90 to 103 called?

actinides

What are the elements with atomic numbers from 58 to 71 called?

lanthanides

Argon, krypton, and xenon are

noble gases

The periodic law states that the physical and chemical properties of elements are periodic functions of their atomic

numbers

The principle that states that the physical and chemical properties of the elements are period functions of their atomic numbers is

the periodic law

Elements in a group or column in the periodic table can be expected to have similar

properties

For elements in groups 1, 2, and 18, the increase in atomic number for successive elements follows the pattern 8, 8, 18, __, 32

18

To which group do fluorine and chlorine belong? (name and group \#)

Group 17; halogens

A horizontal row of blocks in the periodic table is called a

period

Potassium and bromine belong to what period?

4

Identify the sublevels in a period that contains 32 elements

s, p, d, f

How many elements are in a period in which only the s and p sublevels are filled?

8

Because the first energy level only contains the 1s sublevel, the number of elements in this period is

2

Elements to the right side of the periodic table (p-block elements) have properties most associated with

nonmetals

Elements in which the d-sublevel is being filled have the properties of

metals