Which of the following elements is a halogen?
a. Na
b. Br
c. H
d. He
e. Hg
Answer: B
Which of the following elements is a halogen?
a. Na
b. Br
c. H
d. He
e. Hg
a. Na
b. Br
c. H
d. He
e. Hg
How many electrons are present in a tin atom with a mass number of 119?
How many electrons are present in a tin atom with a mass number of 119?
Answer: 50
The symbol for aluminum is
The symbol for aluminum is
Answer: Al
How many electrons are present in a fluorine, F, atom?
How many electrons are present in a fluorine, F, atom?
Answer: 9
Co is the symbol for
Co is the symbol for
Answer: cobalt
Which of the following is a noble gas?
Which of the following is a noble gas?
a. O2
b. CO2
c. Ar
d. H2
e. N2
Answer: C
The symbol for the element calcium is
The symbol for the element calcium is
Answer: Ca
How many atoms totals are indicated in the formula NH4C8H4O2?
How many atoms totals are indicated in the formula NH4C8H4O2?
Answer: 19
Which scientists were instrumental in determining that atoms have a nucleus that is positively charged?
Which scientists were instrumental in determining that atoms have a nucleus that is positively charged?
Answer: Ernest Rutherford
Which pair contains an element that does not exist as a diatomic molecule?
Which pair contains an element that does not exist as a diatomic molecule?
a. hydrogen and oxygen
b. bromine and iodine
c. helium and nitrogen
d. chlorine and fluorine
Answer: C
The noble gases
The noble gases
a. are chemically inert
b. do not form ions
c. exist as diatomic molecules
d. both a and b are correct
Answer: D
What is the most abundant element found in the human body?
What is the most abundant element found in the human body?
Answer: oxygen
The number of protons in the nucleus of an atom is called its
The number of protons in the nucleus of an atom is called its
Answer: atomic number
Which of the following statements are true?
Which of the following statements are true?
I. The number of protons in an element is the same for all neutral atoms of that element.
II. The number of electrons in an element is the same for all neutral atoms of that element.
III. The number of neutrons in an element is the same for all neutral atoms of that element
Answer: Only I and II are true
Which particle has the smallest mass?
Which particle has the smallest mass?
a. neutron
b. electron
c. helium nucleus
d. proton
Answer: B
Which pair has approximately the same mass?
Which pair has approximately the same mass?
a. proton and a neutron
b. a neutron and an electron
c. an electron and a proton
Answer: A
The atom with 68 neutrons and 50 protons has a mass number of
The atom with 68 neutrons and 50 protons has a mass number of
Answer: 118
Who discovered the neutron?
Who discovered the neutron?
Answer: Chadwick
Which of the following elements is an alkali metal?
Which of the following elements is an alkali metal?
a. Cu
b. Ne
c. Fe
d. K
e. Ca
Answer: D
Which of the following would most likely form cations?
Which of the following would most likely form cations?
a. lithium
b. sulfur
c. krypton
d. none of the above
Answer: A
An ion is formed when
An ion is formed when
a. an atom gains one or more protons
b. an atom gains one or more electrons
c. an atom loses one or more electrons
d. either b or c
Answer: D
The chemical formula Ga2O3 indicates
The chemical formula Ga2O3 indicates
a. two atoms of gallium and three atoms of oxygen
b. six atoms of each element
c. three atoms of gallium and two atoms of oxygen
d. five atoms of each element
e. none of the above
Answer: A
The fundamental particle of a chemical element according to Dalton's theory is
The fundamental particle of a chemical element according to Dalton's theory is
Answer: atom
An atom with 16 protons and 16 neutrons is an atom of
An atom with 16 protons and 16 neutrons is an atom of
Answer: S (sulfur)
Which of the following elements is most similar to chlorine?
Which of the following elements is most similar to chlorine?
a. Na
b. Br
c. H.
d. He
e. Hg
Answer: B
Metalloids
Metalloids
a. have some metallic and some nonmetallic properties
b. include all the elements in Group 2A
c. are chemically inert
d. are all liquids
Answer: A
An atom with 46 protons has a mass number of 102. The atom is
An atom with 46 protons has a mass number of 102. The atom is
Answer: Pd
The symbol Fe stands for the element
The symbol Fe stands for the element
Answer: iron
Choose the pair in which the components have the same charge.
Choose the pair in which the components have the same charge.
a. a hydrogen atom and an electron
b. an electron and a neutron
c. a neutron and a hydrogen atom
d. a proton and a hydrogen atom
Answer: C
Which part of the atom determines the chemical reactivity of that atom?
Which part of the atom determines the chemical reactivity of that atom?
Answer: the electrons surrounding the nucleus
Which of the following is a nonmetal?
Which of the following is a nonmetal?
a. chromium
b. carbon
c. calcium
d. cobalt
e. copper
Answer: B
Atoms of the same element having the same atomic number, but different mass numbers, are called
Atoms of the same element having the same atomic number, but different mass numbers, are called
Answer: isotopes
Si is the symbol of
Si is the symbol of
Answer: silicon
The symbol for the element titanium is
The symbol for the element titanium is
Answer: Ti
The symbol for magnesium is
The symbol for magnesium is
Answer: Mg
The first scientist to show that atoms emit tiny negative particles was
The first scientist to show that atoms emit tiny negative particles was
Answer: J. J. Thomson
How does a phosphorus atom become a phosphide ion? Is it a cation or an anion? Is the ion larger or smaller than its atom?
How does a phosphorus atom become a phosphide ion? Is it a cation or an anion? Is the ion larger or smaller than its atom?
Answer: It loses three electrons; anion; larger
Give the name of the element that has a mass number 14 and 8 neutrons.
Give the name of the element that has a mass number 14 and 8 neutrons.
Answer: carbon
The halogen in the third period
The halogen in the third period
Answer: Cl
The transition meal that has 24 electrons as a +3 ion
The transition meal that has 24 electrons as a +3 ion
Answer: cobalt
Cathode rays are
Cathode rays are
A) neutrons
B) x-rays
C) electrons
D) protons
E) atoms
Answer: C
What did Neils Bohr do?
What did Neils Bohr do?
Answer: Niels Bohr created the current model of the atom were electrons are in different energy levels
What did Max Plank do?
What did Max Plank do?
Answer: Discovered energy of Photons is related to their frequency
What did Ernst Rutherford do?
What did Ernst Rutherford do?
Answer: Discovered the nucleus
What did Millikan do?
What did Millikan do?
Answer: Determined the charge of a electron
What did J.J. Thompson do?
What did J.J. Thompson do?
Answer: Discovered electrons
What did John Dalton do?
What did John Dalton do?
Answer: He discovered the atom, but he believed it was just a singe dot of just atom
Which of the following are chemical processes?
Which of the following are chemical processes?
1. Ripening of an apple
2. Freezing water
3. decomposition of water into hydrogen and oxygen gas
4. Compression of oxygen gas
Answer: 1 and 3
What is the difference between an intensive and an extensive property?
What is the difference between an intensive and an extensive property?
Answer: An extensive property is a property an affected by changes in sample size, while intensive are ones that are not affected
Which of the following is not an intensive property?
Which of the following is not an intensive property?
A) Density
B) temperature
C) melting point
D) mass
E) boiling point
Answer: D
In the following list, only _______ is not an example of a chemical reaction.
In the following list, only _______ is not an example of a chemical reaction.
A) Dissolution of a penny in nitric acid
B) the condensation of water vapor
C) a burning candle
D) the formation of polyethylene from ethylene
E) the tarnishing of silver
Answer: B
If matter is uniform throughout and cannot be separated into other substances by physical means, it is
If matter is uniform throughout and cannot be separated into other substances by physical means, it is
A) a compound
B) either an element or a compound
C) a homogeneous mixture
D) a heterogeneous mixture
E) an element
Answer: B
From which of the following can the composition vary
From which of the following can the composition vary
A) Pure substances
B) Element
C) Both homogeneous and heterogeneous mixtures
D) Homogeneous mixture
E) Heterogeneous mixture
Answer: C
Of solids, liquids, and gases which one(s) of these states of matter are significantly compressible
Of solids, liquids, and gases which one(s) of these states of matter are significantly compressible
Answer: Gases
Which one of the following is often easily separated into its components by simple techniques known as filtering
Which one of the following is often easily separated into its components by simple techniques known as filtering
A) Heterogeneous Mixture
B) Compounds
C) homogenois mixtures
B) elements
E) Solutions
Answer: A
Which one of the following is a pure substance?
Which one of the following is a pure substance?
A) Concrete
B) Wood
C) salt water
D) Elemental copper
E) Milk
Answer: D
What two classifications of matter can be considered pure substances?
What two classifications of matter can be considered pure substances?
Answer: Elements and compounds
What are the possible values for the following quantum numbers in an atom?
What are the possible values for the following quantum numbers in an atom?
a. n
b. l
c. ml
Answer:
a. n = 1, 2, 3, ...
b. l = 0, 1, ...., n-1
c. ml = -l, -l+1, ........, +l
The following combinations of quantum numbers are not allowed. Correct each set by changing only one quantum number, and write in an appropriate corrected value.
The following combinations of quantum numbers are not allowed. Correct each set by changing only one quantum number, and write in an appropriate corrected value.
a. n = 2 l = 2 ml = 2 Corrected: _____ = _____
b. n = 4 l = -2 ml = 0 Corrected: _____ = _____
Answer:
a.n=3
b. l = 0 (or 1, 2 or 3)
What are the three stresses that can upset the equilibrium of a system and cause it to shift in favor of the reactants and products?
What are the three stresses that can upset the equilibrium of a system and cause it to shift in favor of the reactants and products?
Answer: changes in concentration of reactants or products, changes in temperature, and change in pressure
How might understanding Le Chatlier's principle help chemists increase the percent yield of a reversible chemical equation?
How might understanding Le Chatlier's principle help chemists increase the percent yield of a reversible chemical equation?
Answer: because is a stress is applied to a system in equilibrium, the system changes in a way to relieve the stress
If the pH is 9, what is the concentration of hydroxide ion?
If the pH is 9, what is the concentration of hydroxide ion?
Answer: 1 x 10^-5 M
If the[H ] in a solution is 1 x 10^-1 mol/L,what is the[OH ]?
If the[H ] in a solution is 1 x 10^-1 mol/L,what is the[OH ]?
Answer: 1 x 10^-13 mol/L
What four factors influence the rate of a chemical reaction?
What four factors influence the rate of a chemical reaction?
Answer: temp, concentration, particle size, and the use of a catalyst
What happens to the amounts of reactants and products after a reaction has reached chemical equilibrium?
What happens to the amounts of reactants and products after a reaction has reached chemical equilibrium?
Answer: they remain constant
What is the function of the water outside the reaction chamber of calorimeter? Why does the water bath in a calorimeter have to be insulated?
What is the function of the water outside the reaction chamber of calorimeter? Why does the water bath in a calorimeter have to be insulated?
Answer: The water is used to keep the temperature of calorimeter stable and constant. It is insulated to block heat from passing through.
Explain why this is not s violation of the law of conservation of energy.
Explain why this is not s violation of the law of conservation of energy.
Answer: You can still account for all the energy used; the energy probably turned into thermal or kinetic energy
When 64 g of methanol (CH3OH) is burned, 1454 kJ of energy is produced. What is the heat of combustion for methanol?
When 64 g of methanol (CH3OH) is burned, 1454 kJ of energy is produced. What is the heat of combustion for methanol?
Answer: 1454 kJ / 64g methanol x 32gmeth / 1 mol meth
The specific heat capacity of graphic is 0.71 J/gc. Calculate the energy required to raise the temperature of 750 g of graphite from 20 C to 180 C.
The specific heat capacity of graphic is 0.71 J/gc. Calculate the energy required to raise the temperature of 750 g of graphite from 20 C to 180 C.
Answer: 750g x 0.71 J/gc x 160 C
What is the difference between a theory and a law? What is the collision theory?
What is the difference between a theory and a law? What is the collision theory?
Answer: a law is a statement of what will happen while a theory explains why something happens. the collision theory states that atoms, ions, and molecule can react to form products when they collide
A thin, 0.2 molsheet of zinc is completely converted to zinc oxide in one month. How would you express the rate of this reaction?
A thin, 0.2 molsheet of zinc is completely converted to zinc oxide in one month. How would you express the rate of this reaction?
Answer: 0.2Zn -> ZNO / 1 month
What particle is needed to complete this nuclear reaction 222 86 Rn -> 218 84 Po + _____
What particle is needed to complete this nuclear reaction
222 86 Rn -> 218 84 Po + _____
Ans :4 2 He
What is the product of this radioactive decay
What is the product of this radioactive decay
Answer: 56 25 Mn -> + 0 -1 e
56 26 Fe
Which of the following is one way that nuclear reactions differ from chemical reactions
Which of the following is one way that nuclear reactions differ from chemical reactions
Answer: Nuclear reactions are not affected by temperature
What is the final product of a sequence of spontaneous nuclear decay reactions
What is the final product of a sequence of spontaneous nuclear decay reactions
Answer: A stable isotope
Which of the following is the same as a beta particle
Which of the following is the same as a beta particle
Answer: Electron
Which symbol is used for an alpha particle
Which symbol is used for an alpha particle
Answer: 4 2 He
What particle is emitted in alpha radiation
What particle is emitted in alpha radiation
Answer: Helium nucleus
Explain the context and meanings of the terms "orbit" and "orbital", making a clear distinction between them.
Explain the context and meanings of the terms "orbit" and "orbital", making a clear distinction between them.
Answer: Orbit is a term from the Bohr theory, and refers to an exact, circular path followed
by an electron. It has been superseded by the concept of an orbital, which arises from the Schrodinger equation. An orbital is a wave function, or, more loosely, a region of space close to the nucleus where an electron is likely to be found.
In the quantum mechanical treatment of the hydrogen atom, the functions and 2 both feature prominently. Briefly explain (in principle) how they are obtained and what, if anything, their physical meanings are.
In the quantum mechanical treatment of the hydrogen atom, the functions and 2 both feature prominently. Briefly explain (in principle) how they are obtained and what, if anything, their physical meanings are.
Solution: The wave function, is a solution to the Schrodinger equation. It describes a wave, but has no physical meaning of its own. The square of the wave function, 2, represents the probability of finding the electron at any point in the atom.
Calculate the momentum of a photon of green light, wavelength 515 nm.
Calculate the momentum of a photon of green light, wavelength 515 nm.
Solution: 1.29 x 10^-27 kg·m/s.wIf this photon is traveling in a vacuum, what is its "mass"?
Solution: 4.29 x 10^-36 kgWhat is the speed of an electron in m/s if its wavelength is 0.155 nm?
What is the speed of an electron in m/s if its wavelength is 0.155 nm?
Answer: 4.69 x 10^6 m/s
Use the Bohr equation to calculate the energy of
Use the Bohr equation to calculate the energy of
Question 1. the largest energy absorption or emission process involving the n = 2 state of the hydrogen atom.
Solution: 1.64 x 10^-18 J
(n = 1 to n = 2)
Question 2: the smallest energy absorption or emission process involving the n = 2 state of the hydrogen atom.
Solution: 3.03 x 10^-19 J
(n = 3 to n = 2)
What is the minimum wavelength of a photon needed for it to have the energy needed in (a)?
What is the minimum wavelength of a photon needed for it to have the energy needed in (a)?
Answer: 91.2 nm
Use the Bohr equation to calculate the energy needed to ionize a hydrogen atom from its ground state.
Use the Bohr equation to calculate the energy needed to ionize a hydrogen atom from its ground state.
Answer: 2.18 x 10^-18 J
If a photon provides the energy in (a), what is its wavelength in nm?
If a photon provides the energy in (a), what is its wavelength in nm?
Answer: 97.2 nm
Use Bohr's equation to calculate how much energy (in J) is needed to promote an electron from the H-atom ground state to the n = 4 level.
Use Bohr's equation to calculate how much energy (in J) is needed to promote an electron from the H-atom ground state to the n = 4 level.
Answer: 2.04 x 10^-18 J
Would the photon in (a) have enough energy to ionize a hydrogen atom in its ground state (i.e., to separate the proton and electron completely)? Use the Bohr equation to explain your answer.
Would the photon in (a) have enough energy to ionize a hydrogen atom in its ground state (i.e., to separate the proton and electron completely)? Use the Bohr equation to explain your answer.
Answer: No. 2.18 x 10^-18 J is needed, the difference between the n = 1 and n = infinity levels.
Calculate the wavelength in nm of a photon whose energy is 6.00 x 10^-19 J.
Calculate the wavelength in nm of a photon whose energy is 6.00 x 10^-19 J.
Answer: 331 nm
Use the Rydberg equation to calculate the wavelength, in nm, of the least energetic (longest wavelength) line in the visible series (n1 = 2) of the spectrum of atomic hydrogen.
Use the Rydberg equation to calculate the wavelength, in nm, of the least energetic (longest wavelength) line in the visible series (n1 = 2) of the spectrum of atomic hydrogen.
Answer: 656 nm
What is the energy of one photon of this radiation?
What is the energy of one photon of this radiation?
Answer: 1.86 x 10^-24 J
What is the frequency of microwave radiation which has a wavelength of 10.7 cm?
What is the frequency of microwave radiation which has a wavelength of 10.7 cm?
Answer: 2.80 x 10^9 s^-1
Based on relative location on the periodic table, vanadium (symbol = V) is expected to have more metallic character than selenium (symbol = Se).
Based on relative location on the periodic table, vanadium (symbol = V) is expected to have more metallic character than selenium (symbol = Se).
Answer: True
Based on relative location on the periodic table, a carbon atom is larger in atomic size than a phosphorous atom.
Based on relative location on the periodic table, a carbon atom is larger in atomic size than a phosphorous atom.
Answer: False
The atomic size of lithium is larger than the atomic size of nitrogen.
The atomic size of lithium is larger than the atomic size of nitrogen.
Answer: True
The ionization energy of lithium is higher than that of fluorine.
The ionization energy of lithium is higher than that of fluorine.
Answer: False
The elements will lose or gain electrons as needed to have an electron configuration that matches a noble gas.
The elements will lose or gain electrons as needed to have an electron configuration that matches a noble gas.
Answer: True
Bromine has 28 core electrons.
Bromine has 28 core electrons.
Answer: True
The element manganese (symbol = Mn) has five valence electrons.
The element manganese (symbol = Mn) has five valence electrons.
Answer: False
The correct electron configuration for magnesium is: 1s22s22p63s3.
The correct electron configuration for magnesium is: 1s22s22p63s3.
Answer: False
The orbital diagram for fluorine shows 1 unpaired electron in a p orbital.
The orbital diagram for fluorine shows 1 unpaired electron in a p orbital.
Answer: True
The Pauli exclusion principle states that orbitals may hold no more than two electrons of identical spins.
The Pauli exclusion principle states that orbitals may hold no more than two electrons of identical spins.
Answer: False
Transition metal elements always contain at least one "d" block electron.
Transition metal elements always contain at least one "d" block electron.
Answer: True
The correct electron configuration for fluorine is: 1s22s22p5.
The correct electron configuration for fluorine is: 1s22s22p5.
Answer: True
The ground state is when an electron in an atom is excited into the lowest possible vacant orbital.
The ground state is when an electron in an atom is excited into the lowest possible vacant orbital.
Answer: False
The subshells s, p, d, and f all have the same energy as long as they are in the same principal shell.
The subshells s, p, d, and f all have the same energy as long as they are in the same principal shell.
Answer: False
A principal shell with a value of n=3 would contain s, p, d, and f orbitals.
A principal shell with a value of n=3 would contain s, p, d, and f orbitals.
Answer: False
The subshells of the orbital are represented by the possible letters: s, p, d, or f
The subshells of the orbital are represented by the possible letters: s, p, d, or f
Answer: True
The possible values for the principal quantum numbers are: n= 0,1,2,3,4
The possible values for the principal quantum numbers are: n= 0,1,2,3,4
Answer: False
The higher the principal quantum number, the lower the orbital energy.
The higher the principal quantum number, the lower the orbital energy.
Answer: False
An orbital is a probability map showing exactly where an electron can be found in an atom.
An orbital is a probability map showing exactly where an electron can be found in an atom.
Answer: False
Electrons behave like particles and we can describe their exact paths.
Electrons behave like particles and we can describe their exact paths.
Answer: False
The energy of each Bohr orbit increases with increasing value of "n," but levels become more closely spaced as "n" increases.
The energy of each Bohr orbit increases with increasing value of "n," but levels become more closely spaced as "n" increases.
Answer: True
The energy of an electron orbit is quantized.
The energy of an electron orbit is quantized.
Answer: True
When an atom absorbs energy, it often re-emits that energy as heat.
When an atom absorbs energy, it often re-emits that energy as heat.
Answer: False
An emission spectrum results when light emitted by glowing gas is passed through a prism.
An emission spectrum results when light emitted by glowing gas is passed through a prism.
Answer: True
Each element produces its own unique and distinctive emission spectrum.
Each element produces its own unique and distinctive emission spectrum.
Answer: True
Bohr showed that the emission spectrum of hydrogen was continuous with no interruption across the entire visible wavelength range.
Bohr showed that the emission spectrum of hydrogen was continuous with no interruption across the entire visible wavelength range.
Answer: False
The great success of the Bohr model of the atom is that it predicted the emission spectrum lines of multi-electronic elements like helium.
The great success of the Bohr model of the atom is that it predicted the emission spectrum lines of multi-electronic elements like helium.
Answer: False
In order for a substance to be heated in a microwave, it must contain water.
In order for a substance to be heated in a microwave, it must contain water.
Answer: True
The heat you feel when you place your hand near a hot object is ultraviolet radiation.
The heat you feel when you place your hand near a hot object is ultraviolet radiation.
Answer: False
Ultraviolet light produces suntans and sunburns.
Ultraviolet light produces suntans and sunburns.
Answer: True
X-rays damage biological molecules.
X-rays damage biological molecules.
Answer: True
Photons of ultraviolet radiation contain more energy than do photons of violet visible light.
Photons of ultraviolet radiation contain more energy than do photons of violet visible light.
Answer: True
Visible light makes up the largest portion of the electromagnetic spectrum.
Visible light makes up the largest portion of the electromagnetic spectrum.
Answer: False
The most energetic photons are gamma rays.
The most energetic photons are gamma rays.
Answer: True
Wavelength of visible light determines color.
Wavelength of visible light determines color.
Answer: True
The shorter the wavelength of light, the more energy it has.
The shorter the wavelength of light, the more energy it has.
Answer: True
A photon of red light contains the same amount of energy as a photon of blue light.
A photon of red light contains the same amount of energy as a photon of blue light.
Answer: False
Blue light travels at a faster speed than red light.
Blue light travels at a faster speed than red light.
Answer: False
A photon represents the mass of a single particle of light.
A photon represents the mass of a single particle of light.
Answer: False
A particle of light is called a packet.
A particle of light is called a packet.
Answer: False
A red shirt appears red to our eyes because the shirt absorbs the red wavelengths of visible light.
A red shirt appears red to our eyes because the shirt absorbs the red wavelengths of visible light.
Answer: False
Light travels through space at a speed of 3.00 × 10^8 m/s.
Light travels through space at a speed of 3.00 × 10^8 m/s.
Answer: True
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