Honors Chemistry 1st semester exam q's
An element that has an electron configuration of [He]2s22p3 is in Period _____ of the periodic table
2
How many of the following electron configurations for the species in their ground state are correct? I. Ca: 1s22s22p63s23p64s2 II. Mg: 1s22s22p63s1 III. V: [Ar]3s23d3 IV. As: [Ar]4s23d104p3 V. P: 1s22s22p63p5
2
The number of orbitals having a given value of l is equal to
2l + 1
How many extra electrons are in the Lewis structure of the phosphate ion, PO43-?
3
How many orbitals have the set of quantum numbers n=4, l =1
3
The number of significant figures in the measured value 0.032 0 g is
3
The number of significant figures in the measurement 0.000 305 kg is
3
Which of the following sets of quantum numbers (n, l, ml, ms) refers to a 3d orbital?
3 2 2 +1/2
An atom of fluorine contains nine electrons. How many of these electrons are in s orbitals?
4
If n = 2, how many orbitals are possible
4
Which of the following could not be a valid ml quantum number for a 4f orbital?
4
hich of the following combinations of quantum numbers (n, l, ml, ms) do not represent permissible solutions of the Schrödinger equation for the electron in the hydrogen atom (i.e., which combination of quantum numbers is not allowed)?
6, -5, -1, 1/2
What is the frequency of photons that have molar energy of 243 kJ/mol?
6.09 x 10^14 Hz
For the f sublevel, the number of orbitals is
7
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
How many orbitals can exist at the third main energy level?
9
Which of the following is a correct Lewis structure for oxygen?
: O = O : .. ..
Which letter above represents the s block elements
A
The formula for aluminum bromide is
AlBr3.
To which group of the periodic table do lithium and potassium belong?
Alkali Metals
How many electrons in an atom can have the quantum numbers n = 4, l = 2?
10
The atomic number of the first element in Period 3, is 11. The atomic number of the second element in this period is
12
What are the bond angles in CO32-?
120º
Water is contained in glaciers as ice. Complete the sentence below using one of the answers provided. For liquid water to be formed from the glaciers . ..
energy is required.
A theory is a(n) ____.
explanation supported by many experiments.
An atom becomes negatively charged by _____.
gaining an electron.
What is the trend in atomic radii as you move from left-to-right across a period?
generally decreases
The elements in Group 17 are known by what name?
halogens
How many lone pairs of electrons are on the sulfur atom in sulfite ion, SO32-?
1
How should you prepare an acid solution?
Add the acid to the water very slowly.
In metallic bonds, the mobile electrons surrounding the positive ions are called a(n)
Electron Sea
What are shared in a covalent bond?
Electrons
Binary molecular compounds are generally composed of a metal and a nonmetal.
False
Energy is not stored in food. Food only gives you energy when you eat it.
False
The majority of the elements in the periodic table are nonmetals.
False
In a discussion about stored energy, students agree that both beans and coal have stored energy. The teacher then asked, "Where did the energy come from that is stored in beans and coal?"
From the sun's light
Which of these metric units is used to measure mass?
G
Which type of electromagnetic radiation has the highest energy?
Gamma Rays
Which of the following molecules are polar: H2S, CO2, NH3, BH3, and CCl4?
H2S and NH3
"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
Hund's rule.
Scientists believe that the universe contains all the matter and energy that ever existed.
True
When energy is transformed from one kind to another, some of it may change to heat.
True
In what form do elements such as hydrogen, nitrogen, and oxygen normally occur?
as molecules containing two atoms
Bond length is the average distance between two bonded atoms
at which potential energy is at a minimum.
A chemical bond formed by the attraction between positive ions and surrounding mobile electrons is a(n)
metallic bond.
Malleability and ductility are characteristic of substances with
metallic bonds.
Which type of electromagnetic radiation has the longest wavelength?
microwaves
What values can the angular momentum quantum number have when n = 2?
0, 1
Which of the following is/are true about electromagnetic radiation? 1. Wavelength is inversely proportional to frequency. 2. Frequency has units of s-1 or Hz. 3. Waves of different wavelengths travel at different speeds in a vacuum.
1 and 2
The outer electron configuration of an alkali metal has
1 electron in the s orbital.
Which of the following statements concerning quantum mechanics is/are true?
1. The behavior of submicroscopic particles can sometimes be described as waves. 2. Quantum mechanics limits us to making statistical statements about the location of an electron in an atom.
Which of the following is a correct Lewis structure for C2H6O?
Answers A and C are correct
What is the correct formula for bismuth(III) sulfite?
Bi2(SO3)3
Your class is beginning a unit on energy flow in natural systems. At the end of the unit, a test includes the following questions about the food chain shown below. What kind of energy passed from one living thing to another?
Chemical/Potential energy
The formula for copper(II) phosphate is
Cu3(PO4)2.
Which letter above represents the f block elements
D
When an electron in an atom makes a transition from n = 3 to n = 2, which of the following statements is/are correct? I. Energy is emitted. II. Energy is absorbed. III. The electron loses energy. IV. The electron gains energy. V. The electron cannot make this transition.
I. Energy is emitted. II. Energy is absorbed.
Consider the following energy-level diagram for a particular electron in an atom. Based on this diagram, which of the following statements is incorrect?
If the electron is in level 1, it may jump to level 2 by absorbing any photon having energy of at least DE.
An object that has kinetic energy must be....
In motion
Which of the following is a reasonable criticism of the Bohr model of the atom?
It does not adequately predict the ionization energy of the valence electron(s) for elements other than hydrogen.
Ni has two unpaired electrons in its 3d orbitals.
It is a true statement
As the energy of a photon increases, its frequency decreases
It is incorrect
Energy is measured in units of
Joules
Which of the following is the best example of increasing an object's potential energy?
Stretching a rubberband
From the Bohr model of the hydrogen atom, we can conclude that the energy required to excite an electron from n = 2 to n = 3 is ____ the energy required to excite an electron from n = 1 to 2.
Less than
Your class is beginning a unit on energy flow in natural systems. At the end of the unit, a test includes the following questions about the food chain shown below. What is the ultimate kind of energy that supports this food chain?
Light/Radiant Energy
Use VSEPR theory to predict the shape of carbon dioxide, CO2.
Linear
Which of the following elements is a metal?
Magnesium
According to ____ periodic table, the physical and chemical properties of elements are periodic functions of their atomic weights.
Mendeleev
A neutral group of atoms held together by covalent bonds is a
Molecule
The following molecules contain polar bonds. The only polar molecule is
NH3.
The substance whose Lewis structure shows three covalent bonds is
NH3.
Which of the following is an ionic compound?
NH4CN
Most of the elements in groups 6A-8A (16-18) are classified as ____.
Nonmetal
Below is a diagram from a science textbook of two metal blocks side-by-side. The teacher tells students that metal Block 1 is at a temperature of 100 degrees F; a block the same size, Block 2, is 20 degrees F. Students observe the drawing. Then the teacher says, "Which of the following explanations describe what will happen?" Students must first come to an agreement on which explanation is best. Then the teacher must agree with their reasons for their answer. Which of the explanations below should the teacher accept as correct?
Only heat will flow from Block 1 to Block 2.
Trends in the periodic table indicate that an element in which of the following periods and groups will have the smallest anion (negative ion) radius?
Period 1, Group 17
Trends in the periodic table indicate that the element with the greatest ionization energy is in which of the following periods and groups?
Period 1, Group 18
Trends in the periodic table indicate that an element in which of the following periods and groups will have the largest cation (positive ion) radius?
Period 7, Group 1
If the atoms that share electrons have an unequal attraction for the electrons, the bond is called
Polar
Your class is beginning a unit on energy flow in natural systems. At the end of the unit, a test includes the following questions about the food chain shown below.
Some of the energy transferred from the Sun to the grass to the deer.
Hot glass looks the same as cold glass.
True
A teacher recently introduced a new science unit on motion energy (kinetic energy). She asked students to tell her what they knew about motion energy. Below are five responses. Which do you consider the most accurate response? KE = 1/2 mv2
The motion energy (kinetic energy) of an object depends on its mass and the speed of the object.
Which is the best reason that the atomic radius generally increases with atomic number in each group of elements?
The number of energy levels increases.
Which of the following is not determined by the principal quantum number, n, of the electron in a hydrogen atom?
The size of the corresponding atomic orbital(s).
When a particular metal is illuminated with photons, one electron is observed for each absorbed photon. What effect would decreasing the wavelength and number of photons have on the electrons leaving the surface?
They would have higher kinetic energy.
When filling orbitals of equal energy, two electrons will occupy the same orbital before filling a new orbital.
This statement is false
Germanium has __________ in its 4p orbitals
Two electrons
Ti has __________ in its d orbitals.
Two electrons
Compared with molecular bonds, the strength of intermolecular forces is
Weaker
The electron configuration for the barium atom is
[Xe]6s2
An ionic bond is ____.
a force that holds together atoms that are oppositely charged.
Which of the following best describes temperature?
a measure of the average kinetic energy of the particles in a sample of matter
Which of the following is most likely to produce data that are not precise?
altering the procedure during an experiment
Standards of measurement are chosen because they
are reproducible in another laboratory.
The law of __________________ of energy states that energy cannot be created or destroyed
conservation
The ions in most ionic compounds are organized into a
crystal.
At the end of an experiment, the scientist forms a conclusion based on the
data obtained.
As atoms bond with each other, they
decrease their potential energy, thus creating more-stable arrangements of matter.
When a stable covalent bond forms, the potential energy of the atoms
decreases
From the following list of observations, choose the one that most clearly supports the following conclusion: a) emission spectrum of hydrogen b) the photoelectric effect c) scattering of alpha particles by metal foil d) diffraction e) cathode "rays"
diffraction
The strong forces of attraction between the positive and negative regions of molecules are called
dipole-dipole forces.
Elements in a group have similar
electron configurations.
Compared with ionic compounds, molecular compounds
have lower melting points.
For the alkaline-earth metals, atoms with the smallest radii have the (Think Trends)
highest ionization energies.
The shiny appearance of a metal is most closely related to the metal's
highly mobile valence electrons.
Because c, the speed of electromagnetic radiation, is a constant, the wavelength of the radiation is
inversely proportional to its frequency.
A(n) _____ is an atom, or bonded group of atoms, that has a positive or negative charge.
ion
All of the following describe the Schrödinger wave equation except
it is similar to Bohr's theory.
Ignoring friction, at what point in its motion is the kinetic energy of the ball at a maximum?
just after the bat strikes it
Both the Heisenberg uncertainty principle and the Schrödinger wave equation
led to the concept of atomic orbitals.
Based on the photoelectric effect, Einstein proposed the idea that
light has particle-like properties.
Compared with energies of neutral atoms, a crystal lattice has
lower potential energy.
Given the following set of two quantum numbers for a multi-electron atom: 2, 0, 0, 1/2 & 2, 0, 0, -1/2 What are the n and l quantum numbers for the next higher energy electron in this ground state atom?
n = 2, l = 1
Which of the following combinations of quantum numbers is permissible?
n = 3, l = 2, ml = 1, ms = -1/2
Name the compound Ni(ClO3)2.
nickel(II) chlorate
If two covalently bonded atoms are identical, the bond is
nonpolar
Atomic radii cannot be measured directly because the electron cloud surrounding the nucleus does not have a clearly defined _____.
outer edge.
The set of orbitals that are dumbbell shaped and directed along the x, y, and z axes are called
p orbitals.
Mendeleev is credited with developing the first successful
periodic table.
Choose the name-formula pair that does not match.
potassium permanganate, K2MnO4
These values were recorded as the mass of products when a chemical reaction was carried out three separate times: 8.83 g; 8.84 g; 8.82 g. The mass of products from that reaction is 8.60 g. The values are
precise, but not accurate
The chemical formula for an ionic compound represents the
ratio of the combined ions present in a sample.
Bonding in molecules or ions that cannot be correctly represented by a single Lewis structure is
resonance.
The angular momentum quantum number indicates the
shape of an orbital.
For numbers less than 0.1, such as 0.06, the zeros to the right of the decimal point but before the first nonzero digit
show the decimal place of the first digit.
A control is a ____.
standard for comparison.
Use VSEPR theory to predict the shape of the carbon tetraiodide molecule, CI4.
tetrahedral
The statement that an electron occupies the lowest available energy orbital is
the Aufbau principle.
Heat radiated by the Sun warms Earth's surface, which primarily heats . ..
the atmosphere
The greater the average kinetic energy of the particles in a sample of matter,
the higher the temperature is
The periodic law states that
the physical and chemical properties of the elements are functions of their atomic numbers.
VSEPR theory is a model for predicting
the shape of molecules.
Which of the following best describes an orbital?
the space in an atom where an electron is most likely to be found
Use VSEPR theory to predict the shape of the chlorate ion, ClO3-.
trigonal-pyramidal
According to VSEPR theory, the structure of the ammonia molecule, NH3, is
trigonal-pyramidal.
Which of the following classifications describes the element with the electron configuration [Ar]4s23d104p5
unstable nonmetal
The electrons involved in the formation of a chemical bond are called
valence electrons.
