Download Unit 6 Regents Level

Name:___________________________________
Mrs. Bonanno
Chemistry
Pearl River High School
Unit 6 –
The Atom
Vocabulary:
Atom:____________________________________________________________________________________
Nucleus:__________________________________________________________________________________
Neutrons:_________________________________________________________________________________
Protons:__________________________________________________________________________________
Electrons:_________________________________________________________________________________
Nucleons:_________________________________________________________________________________
Atomic Mass:______________________________________________________________________________
Atomic Number:____________________________________________________________________________
Isotopes:__________________________________________________________________________________
Ground State:______________________________________________________________________________
Excited State:______________________________________________________________________________
Ions:_____________________________________________________________________________________
Bright line Spectra:__________________________________________________________________________
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1) Subatomic Particles
a) All atoms are composed of a _______________, _____________, _________________ charged nucleus
that is surrounded by a _________________________ occupied by __________________.
b) The nucleus contains ____________________. There are two types of nucleons:
i) Protons = ___________________________
ii) Neutrons =__________________________
c) Electrons:
i) Occupy the space __________________________________
ii) Have a charge equal to, but opposite of, a proton.
(1) Therefore, an electron is _________________________ charged.
d) Diagram an atom:
a) Elements on the Periodic Table:
a) Atomic Number:_______________________________________________
b) Atomic Mass:_________________________________________________
c) Examples:
Carbon
Flourine
Oxygen
2) Atomic Mass Unit
a) The mass of a proton is only ____________________________________
b) Since the mass is so small we use a different scale called ____________________________________,
to represent mass.
c) Protons:
i) The mass of a proton = _________________________
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d) Neutrons:
i) The mass of a neutron is approximately the same as a proton so its mass is _____________
e) Electrons:
i) Much ____________ massive than a proton or neutron.
ii) Its mass is only ____________ amu
f) Selected Subatomic Particles:
Particle
Charge
Mass
Location
Symbol
Proton
Neutron
Electron
Practice Questions:
1) The atomic number of any atom is equal to the number of
1. neutrons in the atom, only
2. protons in the atom, only
3. neutrons plus protons in the atoms
4. protons plus electrons in the atom
2) What is the symbol for an atom containing 20 protons and 22 neutrons?
1.
2.
3.
4.
3) Which statement best describes an electron?
1. It has a smaller mass than a proton and a negative charge.
2. It has a smaller mass than a proton and a positive charge.
3. It has a greater mass than a proton and a negative charge.
4. It has a greater mass than a proton and a positive charge.
4) What is the mass number of an atom which contains 28 protons, 28 electrons and 34 neutrons?
1. 28
2. 56
3. 62
4. 90
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5) What is the total number of electrons present in an atom of
1. 27
2. 32
3. 39
4. 86
?
6) How many protons are in the nucleus of an atom of beryllium?
1. 5
2. 2
3. 9
4. 4
7) Which particles account for most of the mass of the atom?
1. protons and neutrons
2. protons and electrons
3. neutrons and electrons
4. neutrons and positrons
8) Compared to the entire atom, the nucleus of the atom is
1. smaller and contains most of the atom’s mass
2. smaller and contains little of the atom’s mass
3. larger and contains most of the atom’s mass
4. larger and contains little of the atom’s mass
9) An electron has a charge of
1. −1 and the same mass as a proton
2. +1 and the same mass as a proton
3. −1 and a smaller mass than a proton
4. +1 and a smaller mass than a proton
10) Which species contains only 12 nucleons in the nucleus?
1.
2.
3.
4.
11) Which particle has a mass of approximately one atomic mass unit and a unit positive charge?
1. a neutron
2. a proton
3. a beta particle
4. an alpha particle
12) What is the total number of neutrons in an atom of
1. 82
2. 125
3. 207
4. 289
?
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Atom
#
Protons
#
Neutrons
#
Electrons
Mass
Number
Atomic
Number
Nuclear
Charge
#
Nucleons
Sb
C
Mg
Pb
Pt
F
Ba
Bi
Cm
Si
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3) Isotopes
a) ___________________ of a given element must contain the _____________ number of protons.
b) However, the number of ______________________________________
i) Isotopes: Atoms of the ________________________ that have different numbers of
_____________
(1) Therefore, isotopes have different _____________ numbers!
(2) Isotopes of Hydrogen:
Particle
Protons
Protium
1
Neutrons
Symbol
1 amu
Deuterium
Tritium
Mass Number
1
1
2 amu
2
c) Identifying Isotopes
i) Isotopes are written by using elements ________________ and its _________________________
C-13
Cl – 37
Na - 22
d) Atomic Masses
i) In order to determine the atomic mass of an element, you must ______________________________
of all the _____________________ of that ________________________
ii) Examples:
1) Carbon has ________________________ occurring stable isotopes. Most carbon atoms,
98.89%, are C-12 while the remaining 1.108% are C-13. What is the atomic mass of carbon?
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2) Example: Base your answer on the data table, which shows three isotopes of neon.
Based on natural abundances, what is the average atomic mass of neon?
3) Naturally occurring elemental carbon is a mixture of isotopes. The percent composition of the two most
abundant isotopes is listed below.
98.93% of the carbon atoms have a mass of 12.00 atomic mass units.
1.07% of the carbon atoms have a mass of 13.00 atomic mass units.
What is the average atomic mass of carbon?
4) Atoms of the same element that have different numbers of neutrons are classified as
1. charged atoms
2. charged nuclei
3. isomers
4. isotopes
5) All the isotopes of a given atom have
1. the same mass number and the same atomic number
2. the same mass number but different atomic numbers
3. different mass numbers but the same atomic number
4. different mass numbers and different atomic numbers
6) The atomic mass of an element is defined as the weighted average mass of that element’s
1. most abundant isotope
2. least abundant isotope
3. naturally occuring isotopes
4. radioactive isotopes
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7) An atom that contains 8 protons, 8 electrons, and 9 neutrons has
1. an atomic number of 9
2. an atomic number of 16
3. a mass number of 17
4. a mass number of 25
8) Which two atoms are isotopes?
1.
2.
and
and
3.
and
4.
and
9) Neutral atoms of 35Cl and 37Cl differ with respect to their number of
1. electrons
2. protons
3. neutrons
4. positrons
10) What is the structure of a krypton-85 atom?
1. 49 electrons, 49 protons, and 85 neutrons
2. 49 electrons, 49 protons, and 49 neutrons
3. 36 electrons, 36 protons, and 85 neutrons
4. 36 electrons, 36 protons, and 49 neutrons
11) An atom of carbon-14 contains
1. 8 protons, 6 neutrons and 6 electrons
2. 6 protons, 6 neutrons and 8 electrons
3. 6 protons, 8 neutrons and 8 electrons
4. 6 protons, 8 neutrons and 6 electrons
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Complete the following sentences:
1. Atoms are composed of ________________, _________________, and ________________.
2. The ________________ & ______________ are located in the nucleus, while
the _____________ are outside of the nucleus.
3. Atoms are mostly ___________________________.
4. The number of protons is referred to as the __________________ for the atom.
5. All atoms of the same element have the same number of __________________.
6. Isotopes have the same number of ___________________, but a different
number of ____________________.
7. The mass number of an element is the total number of ________________ &
_________________.
8. Why is the atomic mass of an element given in decimal form in the
periodic table? ________________________________________________
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Determining the number of electrons:
a) Neutral atom
ii) The number of protons is exactly _______________ to the number of electrons.
iii) So the number of ________________ is the same as the _______________ number.
b) Charged Atom = Ion
i) Ion = charged particles created when an atom____________________________ electrons, giving it
a charge!!!
ii) Ions are written with a __________ and the _____________________ that were removed or gained.
iii) If the charge is positive, electrons were ____________________
(1) ______________________ always lose their electrons! So metals always have a ____ charge.
(a) Examples:
iv) If the charge is negative, electrons were ____________________
(1) ____________________ always gain electrons! So nonmetals always have a ______ charge.
(a) Examples:
Practice:
1) The total number of electrons in a
neutral atom of every element is
always equal to the atom’s
1. mass number
2. number of neutrons
3. number of protons
4. number of nucleons
2) What is the total number of
electrons in a Cu+ ion?
1. 28
2. 29
3. 30
4. 36
3) What is the total number of
protons in the nucleus of an F− ion?
1. 8
2. 9
3. 10
4. 11
4) An ion with 5 protons, 6
neutrons, and a charge of 3+ has an
atomic number of
1. 5
2. 6
3. 8
4. 11
5) As a Ca atom undergoes oxidation to
Ca2+, the number of neutrons in its nucleus
1. decreases
2. increases
3. remains the same
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c) Location of Electrons (Based on Wave Mechanical Model)
c) Electrons are found in the _______________ around the nucleus called ____________________
d) Orbitals are arranged by energy levels, each containing a ________________________________
i) The first orbital is called the __________________________
(1) The first energy level contains a maximum of __________________
ii) The second orbital is called the ________________________
(1) The second energy level contains a maximum of _______________
iii) The third orbital is called the __________________________
(1) The third energy level contains a maximum of _________________
iv) The fourth orbital is called the _________________________
(1) The fourth energy level contains a maximum of ________________
d) Electron Configuration
i) Tells how many electrons an atom of a specific element has.
ii) Listed on the periodic table for each element on the bottom left corner.
iii) Listed in order of energy levels
(1) Example:
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iv) The outer most electrons are called the valence electrons
(1) Example:
Na
v.
S
Determine the electron configuration for the following ions:
a. B+ ____________________
b. Cl- ____________________
c. Ca2+____________________
d. O3- ____________________
Practice Questions
1) Which electron configuration is correct for a sodium ion?
1. 2–7
2. 2–8
3. 2–8–1
4. 2–8–2
2) A particle of matter contains six protons, seven neutrons, and six electrons. This particle must be a
1. neutral carbon atom
2. neutral nitrogen atom
3. positively charged carbon ion
4. positively charged nitrogen ion
3) Compared to an element of calcium-40, an atom of potassium-39 contains fewer
1. protons
2. neutrons
3. occupied sublevels
4. occupied principal energy levels
4) Which particle contains the greatest number of electrons?
1. Na
2. Na+
3. F
4. F-
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e) Ground and Excited States
c) Electrons are able to gain or lose energy which allows them to move to different energy levels.
i) How it works:
(1) Electrons __________________________, allowing it to move to a higher energy level.
(2) Electrons __________________________, allowing them to move down to a lower energy level.
(a) The energy given off could be infrared, ultraviolet, or visible light.
d) Ground State
i) When electrons occupy the __________________________, it is in the ground state.
e) Excited State
i) Electrons may _______________________ and temporarily move to a _____________ energy level.
(1) This could be due to _____________________________________________
(2) This unstable state is called the ______________________________
ii) After the electron quickly returns to the _______________________, it ____________ the same
amount of energy it absorbed.
(1) The energy given off is _________________________ that humans can see.
(a) Although the light appears as ________________, it is actually composed of many
___________________ having different __________________
iii) Bright Line Spectra
(1) A tool used to ____________________________ into narrow lines of color called the
_____________________________
(2) This information about the bright line spectra is used to __________________________
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Practice Problems:
1) The bright-line spectra for three elements and a mixture of elements are shown below.
Identify all the elements in the mixture.
2) Base your answer to this question on the information below.
In a laboratory, a glass tube is filled with hydrogen gas at a very low pressure. When a scientist applies a high
voltage between metal electrodes in the tube, light is emitted. The scientist analyzes the light with a
spectroscope and observes four distinct spectral lines. The table below gives the color, frequency, and energy
for each of the four spectral lines. The unit for frequency is hertz, Hz.
Explain, in terms of subatomic particles and energy states, why light is emitted by the hydrogen gas.
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