Chapter 03
A certain isotope X contains 23 protons and 28 neutrons. What is the mass number of this isotope? Identify the element.
Mass number: 51 Element: Vanadium
Most elements found in nature exist in isotopic forms, with the number of naturally occurring isotopes ranging from 2 to 10.
Most elements found in nature exist in isotopic forms, with the number of naturally occurring isotopes ranging from 2 to 10.
Indicate which subatomic particle(s) correctly matches the following phrase: Has no charge
Neutron
pauli exclusion principle
No more than 2 electrons may exist in a single orbital. They also need to have opposite spins.
True or False? All orbitals can accommodate the same number of electrons.
True. Each orbital can only hold two electrons.
highest atomic number of all elements?
Uranium has an atomic number of 92.
How many electrons can be placed in the following: The 4f orbital
2 4f subshell can hold 14 but the orbital itself can only hold 2.
two most common classification systems of elements
1. A system based on selected physical properties of the elements, in which they are described as metals or nonmetals. 2. A system based on the electron configurations of the elements, in which elements are described as noble-gas, representative, transition, or inner transition elements.
three rules for assigning electrons to shells, subshells, and orbitals
1.Electron subshells are filled in the order of increasing energy. 2. Electrons occupy the orbitals of a subshell such that each orbital acquires one electron before any orbital acquires a second electron. All electrons in such singly occupied orbitals must have the same spin. 3. No more than two electrons may exist in a given orbital—and then only if they have opposite spins.
How many electrons can be placed in the following: A d sublevel
10
How many electrons can be placed in the following: The n=1 electron shell
2
An atom has an atomic number of 5 and a mass number of 11. Determine the number of protons present.
5 atomic number = number of protons
An atom has an atomic number of 5 and a mass number of 11. Determine the number of electrons present.
5 number of electrons = atomic number
How many electrons can be placed in the following: The 2p subshell
6
An atom has an atomic number of 5 and a mass number of 11. Determine the number of neutrons present.
6 number of neutrons = mass number - atomic number
How many electrons can be placed in the following: The second shell
8 2(2)^2
alkali metals
A general name for any element in Group IA of the periodic table, excluding hydrogen. Soft, shiny metals that readily react with water.
alkaline earth metal
A general name for any element in Group IIA of the periodic table. Soft, shiny metals that moderately react with water.
halogen
A general name for any element in Group VIIA of the periodic table. Reactive elements that are gases at room temperature or become such at temperatures slightly above room temperature
noble gas
A general name for any element in Group VIIIA of the periodic table. Unreactive gases that undergo few, if any, chemical reactions.
period
A horizontal row of elements in the periodic table.
metal
A metal is an element that has the characteristic properties of luster, thermal conductivity, electrical conductivity, and malleability. With the exception of mercury, all metals are solids at room temperature (25 C). Metals are good conductors of heat and electricity. Most metals are ductile (can be drawn into wires) and malleable (can be rolled into sheets). Most metals have high luster (shine), high density, and high melting points.
orbital diagram
A notation that shows how many electrons an atom has in each of its occupied electron orbitals.
element
A pure substance in which all atoms present have the same atomic number.
electron shell
A region of space about a nucleus that contains electrons that have approximately the same energy and that spend most of their time approximately the same distance from the nucleus. Electron energy increases as the distance of the electron shell from the nucleus increases. 2n^2 to determine number of electrons shell can hold.
electron subshell
A region of space within an electron shell that contains electrons that have the same energy. Subshell size: s subshell can hold 2 electrons. p subshell can hold 6 electrons. d subshell can hold 10 electrons. f subshell can hold 14 subshell. The number of subshells within a shell is the same as the shell number. Shell 1 contains one subshell, shell 2 contains two subshells, shell 3 contains three subshells, and so on.
electron orbital
A region of space within an electron subshell where an electron with a specific energy is most likely to be found.
electronic configuration
A statement of how many electrons an atom has in each of its electron subshells.
neutron
A subatomic particle that has no charge associated with it; that is, it is neutral.
electron
A subatomic particle that possesses a negative (-) electrical charge. Smallest, in terms of mass, of the three subatomic particles. Other two are 2000 times heavier. It has 1/2000th the weight of other two.
proton
A subatomic particle that possesses a positive (+) electrical charge.
periodic table
A tabular arrangement of the elements in order of increasing atomic number such that elements having similar chemical properties are positioned in vertical columns.
group
A vertical column of elements in the periodic table.
subatomic particle
A very small particle that is a building block for atoms.
How many electrons can a orbital accommodate? A. 2 B. 6 C. 10 D. no correct response
A. 2
The atomic number for an atom containing neutrons and protons is A. 8 B. 10 C. 18 D. no correct response
A. 8
Which of the following statements about metallic and nonmetallic elements is correct? A. The vast majority of elements are metals. B. The vast majority of elements are nonmetals. C. Approximately the same number of metallic and nonmetallic elements exist. D. no correct response
A. The vast majority of elements are metals.
The identity of an atom is determined by the number of A. protons in the nucleus B. neutrons in the nucleus C. subatomic particles in the nucleus D. no correct response
A. protons in the nucleus
the number of protons = the number of electrons
An atom as a whole is electrically neutral; that is, it has no net electrical charge.
nonmetal
An element characterized by the absence of the properties of luster, thermal conductivity, electrical conductivity, and malleability most nonmetals are gases. The only nonmetal that is a liquid at room temperature is bromine. Solid nonmetals include carbon, iodine, sulfur, and phosphorus. Nonmetals have lower densities and lower melting points than metals. 23 nonmetals.
transition element
An element located in the d area of the periodic table. All transition elements are metals.
inner transition element
An element located in the f area of the periodic table.
noble gas element
An element located in the far right column of the periodic table.
representative element
An element located in the s area or the first five columns of the p area of the periodic table.
nucleon
Any subatomic particle found in the nucleus of an atom. Thus both protons and neutrons are nucleons, and the nucleus can be regarded as containing a collection of nucleons (protons and neutrons).
electron spin
As an electron moves about within an orbital, it spins on its own axis in either a clockwise or a counterclockwise direction. When two electrons are present in an orbital, they always have opposite spins.
isotopes
Atoms of an element that have the same number of protons and the same number of electrons but different numbers of neutrons. Always have the same atomic number and different mass numbers. Have the same chemical properties (because they have the same number of electrons), but their physical properties are slightly different (because they have different numbers of neutrons).
An atom that has an atomic number of 11 and a mass number of 23 contains how many neutrons? A. 11 B. 12 C. 23 D. no correct response
B. 12
Which of the following statements concerning an atom's nucleus is correct? A. It contains all protons and all electrons. B. It is always positively charged. C. It accounts for most of the total volume of an atom. D. no correct response
B. It is always positively charged.
An electron configuration is a statement of how many electrons an atom has in each of its A. electron shells B. electron subshells C. electron orbitals D. no correct response
B. electron subshells
A standard periodic table arranges the elements in order of A. year of discovery B. increasing atomic number C. increasing reactivity with oxygen D. no correct response
B. increasing atomic number
Atoms of an element that contain a different number of neutrons are known as: A. nucleophiles B. isotopes C. isophiles D. neutrophiles.
B. isotopes
Isotopes of an element always have the A. same mass number and different atomic numbers B. same atomic number and different mass numbers C. different atomic numbers and different mass numbers D. no correct response
B. same atomic number and different mass numbers
Isotopes of an element always have the A. same number of protons and same number of neutrons B. same number of protons and different numbers of neutrons C. same number of neutrons and different numbers of protons D. no correct response
B. same number of protons and different numbers of neutrons
The space in which electrons move rapidly about a nucleus is divided into: A. shells and subshells B. shells, subshells, and orbitals C. shells and orbitals D. subshells and orbitals.
B. shells, subshells, and orbitals
The shape of a 1s orbital is A. circular B. spherical C. figure eight shape D. no correct response
B. spherical
Most atoms contain more neutrons than either protons or electrons.
Because neutrons have no electrical charge, their numbers in atoms do not have to be the same as the number of protons or electrons. The number of neutrons present in atoms of an element is not constant; it varies over a small range. This means that not all atoms of an element have to be identical. They must have the same number of protons and electrons, but they can differ in the number of neutrons.
How are chemical properties of an atom determined?
By the number and arrangement of the electrons about the nucleus. Also, the number of protons (which is the atomic number) characterizes an atom.
How many electrons can a subshell accommodate? A. 2 B. 6 C. 10 D. no correct response
C. 10
Atoms as a whole are neutral because A. The numbers of neutrons exceeds that of protons or electrons. B. Charged subatomic particles lose their charge once they become part of an atom. C. Equal numbers of protons and electrons are present. D. no correct response
C. Equal numbers of protons and electrons are present.
The elements known as halogens and alkali metals are found, respectively, in which groups in the periodic table? A. IA and IIA B. VIA and IIA C. VIIA and IA D. no correct response
C. VIIA and IA
How many electrons are required to equal the mass of one proton? A. 1 B. 23 C. about 1800 D. no correct response
C. about 1800
Which of the following is a general characteristic of most metals? A. low thermal conductivity B. nonductile C. malleable D. no correct response
C. malleable
Which of the following pieces of information about an element is not found on a standard periodic table? A. chemical symbol B. atomic number C. mass number D. no correct response
C. mass number
The element chlorine, which has two isotopic forms, has an atomic mass of 35.5 amu. This means that A. all chlorine atoms have a mass of 35.5 amu B. some, but not all chlorine atoms have a mass of 35.5 amu C. no chlorine atoms have a mass of 35.5 amu D. no correct response
C. no chlorine atoms have a mass of 35.5 amu
The maximum number of electrons that an electron shell can accommodate A. is two B. is ten C. varies, depending on shell number D. no correct response
C. varies, depending on shell number
The maximum number of electron subshells within an electron shell A. is three B. is five C. varies, depending on the shell number D. no correct response
C. varies, depending on the shell number
Groups of elements have similar chemical properties because of similarities in their electron configuration.
Chemical properties repeat themselves in a regular manner among the elements because electron configurations repeat themselves in a regular manner among the elements.
Differences between metals and nonmetals are: A. metals conduct electricity while nonmetals do not B. metals are generally solids while nonmetals exist as gases, liquid, or solids C. metals are malleable while nonmetals are brittle in the solid state D. all of these
D. all of these
Which of the following statements concerning a neutron is correct? A. Its mass is slightly less than that of a proton. B. It carries a positive charge of one unit. C. It carries a positive charge of two units. D. no correct response
D. no correct response
Which of the following statements concerning the three types of subatomic particles is correct? A. All types carry electrical charge. B. One of the three types carries electrical charge. C. None of the three types carry electrical charge. D. no correct response
D. no correct response
The subatomic particles of an atom are: A. protons and neutrons. B. protons and electrons. C. neutrons and electrons. D. protons, neutrons, and electrons.
D. protons, neutrons, and electrons.
Indicate which subatomic particle(s) correctly matches the following phrase: Is not found in the nucleus
Electron
Indicate which subatomic particle(s) correctly matches the following phrase: Possesses a negative charge
Electron
three types of subatomic particles
Electron, Proton, Neutron
hund's rule
Electrons occupy the orbitals of a subshell so each orbital acquires one electron before any orbital acquires a second electron. All electrons in such singly occupied orbitals must have the same spin.
True or False? A p orbital has a spherical shape.
False
True or False? All subshells can accommodate the same number of electrons.
False
True or False? The nucleus of an atom accounts for almost all of the volume of the atom.
False
True or False? The nucleus of an atom has an extremely low density compared to that of the atom as a whole.
False
True or False? The nucleus of an atom is neutral.
False
True or False? The number of nucleons present in the nucleus is equal to the number of electrons present outside the nucleus.
False
True or False? The third energy level can accommodate 32 electrons.
False
True or False? All the subshells in a shell have the same energy.
False
True or False? The nucleus of an atom contains only neutrons.
False
True or False? The nucleus of an atom can be positively or negatively charged, depending on the identity of the atom.
False It's always positively charged
For many years, there was no explanation available for either the periodic law or why the periodic table has the shape that it has. It is now known that the theoretical basis for both the periodic law and the periodic table is found in electronic theory. When two atoms interact, it is their electrons that interact. Thus the number and arrangement of electrons determine how an atom reacts with other atoms—that is, what its chemical properties are. The properties of the elements repeat themselves in a periodic manner because the arrangement of electrons about the nucleus of an atom follows a periodic pattern.
For many years, there was no explanation available for either the periodic law or why the periodic table has the shape that it has. It is now known that the theoretical basis for both the periodic law and the periodic table is found in electronic theory. When two atoms interact, it is their electrons that interact. Thus the number and arrangement of electrons determine how an atom reacts with other atoms—that is, what its chemical properties are. The properties of the elements repeat themselves in a periodic manner because the arrangement of electrons about the nucleus of an atom follows a periodic pattern.
An example of Helium ion being negative, neutral, and positive.
He+ 1e- 2p+ 2n0 He 2e- 2p+ 2n0 He- 3e- 2p+ 2n0
aufbau (building up) diagram
Helps you remember what subshell is filled once a previous one is filled.
What is the most abundant element found in the human body? What is the second most?
Iron and zinc. About 80% of iron is in the blood.
dietary minerals
Other than the four elements, body also needs this. The major minerals, seven in number, include four metals and three nonmetals. The four metals, all located on the left side of the periodic table, are sodium, potassium, magnesium, and calcium. The three nonmetals, all Period 3 nonmetals, are phosphorus, sulfur, and chlorine.
Indicate which subatomic particle(s) correctly matches the following phrase: Has a charge equal to, but opposite in sign from, that of an electron
Proton
Indicate which subatomic particle(s) correctly matches the following phrase: Has a mass slightly less than that of a neutron
Proton
Indicate which subatomic particle(s) correctly matches the following phrase: Has a positive charge
Proton
Indicate which subatomic particle(s) correctly matches the following phrase: Has a relative mass of 1837 if the relative mass of an electron is 1
Proton
Indicate which subatomic particle(s) correctly matches the following phrase: Can be called a nucleon
Proton and Neutron
periodic law
States that when elements are arranged in order of increasing atomic number, elements with similar chemical properties occur at periodic (regularly recurring) intervals.
Why are atoms, instead of subatomic particles, considered to be the building block of all matter?
Subatomic particles do not lead an independent existence for any appreciable length of time; they gain stability by joining together to form atoms.
complete chemical notation
The atomic number is placed as a subscript in front of the chemical symbol and the mass number is placed as a superscript in front of the chemical symbol.
The location of any element in the periodic table is specified by giving its group number and its period number.
The element gold, with an atomic number of 79, belongs to Group IB (or 11) and is in Period 6. The element nitrogen, with an atomic number of 7, belongs to Group VA (or 15) and is in Period 2.
distinguishing electron
The last electron added to the electron configuration for an element when electron subshells are filled in order of increasing energy.
atomic number (Z)
The number of protons in the nucleus of an atom. atomic number = number of protons = number of electrons
nucleus
The small, dense, positively charged center of an atom. All protons and all neutrons are found here. Because of that, more than 99.9% of the mass is concentrated here. In relation to volume, the nucleus is 0.00001 the size of the atom.
mass number (A)
The sum of the number of protons and the number of neutrons in the nucleus of an atom. mass number = number of protons + number of neutrons
electron cloud
The volume occupied by the electrons. The motion of the electrons in the extranuclear region determines the volume (size) of the atom in the same way that the blade of a fan determines a volume by its circular motion. The attractive force between the nucleus (positively charged) and the electrons (negatively charged) keeps the electrons within the extranuclear region of the atom. By analogy, the attractive force of gravity keeps the planets in their positions about the sun.
There are 286 isotopes that occur naturally. More than 2000 additional isotopes have been synthesized in the laboratory via nuclear rather than chemical reactions. All these synthetic isotopes are unstable (radioactive). Despite their instability, many are used in chemical research, as well as in medicine.
There are 286 isotopes that occur naturally. More than 2000 additional isotopes have been synthesized in the laboratory via nuclear rather than chemical reactions. All these synthetic isotopes are unstable (radioactive). Despite their instability, many are used in chemical research, as well as in medicine.
True or False? The nucleus accounts for almost all the mass of an atom.
True
True or False? The nucleus of an atom contains all of the "heavy" subatomic particles.
True
atomic mass
atomic mass is the calculated average mass for the isotopes of an element, expressed on a scale where 12/6-C serves as the reference point. For example, if an atom is twice as heavy as 12/6-C, its mass is 24 amu, and if an atom weighs half as much as an atom of 12/6-C, its mass is 6 amu.
What is amu?
atomic mass unit
building block elements
hydrogen, oxygen, carbon, and nitrogen
Which of the four most abundant nonmetals are found in the human body?
hydrogen, oxygen, carbon, and nitrogen Often referred to as "building block elements" ^
number of protons = atomic number = Z number of electrons = atomic number = Z number of neutrons = mass number - atomic number = A - Z
number of protons = atomic number = Z number of electrons = atomic number = Z number of neutrons = mass number - atomic number = A - Z
The unit smallest by electron capicity?
orbital
This unit can contain a maximum of 2 electrons.
orbital (or s subshell)
Which two nonmetals are most abundant in the Earth's crust?
oxygen and silicon
This unit is also known as the energy level.
shell
This unit is designated by a number.
shell
This unity is designated by a letter.
subshell