4.18 Isotopes
There are _____ neutrons in the stable isotope of rhenium (Re-185).
110
The number of neutrons in U-239 (hybrid notation) will be...
147
How many neutrons are present in the isotope of nobelium, No-254? Nobelium's atomic number is 102.
152
All oxygen atoms have eight protons. What is the mass number of an oxygen isotope that has nine neutrons? What is the name of this isotope?
17, Oxygen-17
You will need to obtain a periodic table. One isotope of copper is written as copper-63. Each atom of this copper isotope contains ____ protons, ____ electrons, and ____ neutrons.
29, 29, 34
You will need to obtain a periodic table. Tin is an example of an element that has a great number of naturally occurring isotopes. How many neutrons are in tin-119?
69
You will need to obtain a periodic table. Tin is an example of an element that has a great number of naturally occurring isotopes. How many neutrons are in tin-120?
70
O-18 has an atomic number of 8. Which of the following shows the correct number of protons, electrons, and neutrons, respectively, in a neutral oxygen atom?
8, 8, 10
The isotopes of an element have the same _____ number.
Atomic
Isotopes are...
Atoms that have the same atomic number, but different mass numbers due to a change in the number of neutrons
Isotopes differ in their:
Both A and B (mass numbers and number of neutrons)
Which of the following does not change in isotopes?
Both A and B (number of electrons and protons)
Hyphen notion is...
Element name - mass #
Different isotopes of the same element have different chemical properties.
FALSE
Since an element always has a different number of protons, the mass can indicate how many neutrons are in an isotope.
FALSE
The introduction of a neutron into the nuclear composition of an atom would lead to a change in its atomic number.
FALSE
The isotopes of an element have different atomic numbers?
FALSE
The number of protons is equal to the mass number of the element.
FALSE
Who discovered isotopes by coining it from the Greek roots "isos" (equal) and "topos" (place)?
Frederick Soddy (1877-1956)
Atoms with different numbers of neutrons but the same number of protons are called...
Isotopes
Atoms with the same atomic number but different mass numbers are called
Isotopes
There are two common isotopes of the element lithium. The first isotope has 3 protons and 3 neutrons. The second isotope has 3 protons and 4 neutrons. Using the hyphenated notation, what are the names of these two isotopes, respectively?
Lithium-6 and Lithium-7
When two or more atoms differ only in the number of neutrons that each contains, what property or properties change?
Mass only
How many neutrons does the deuterium isotope have?
One
Isotopes with an unstable nucleus are called...
Radioactive isotopes
Atomic mass unit is used to calculate the atomic mass of an element or its isotope.
TRUE
Atoms of the same element can have a different number of neutrons.
TRUE
There are three naturally-occurring isotopes of carbon.
TRUE
Nuclide refers to...
The nucleus of a given isotope of an element
The chemical properties of a given element are dictated by:
The number of protons and the number of electrons
The atomic mass of an atom equals what?
The sum of the protons and the neutrons
Why are the atomic masses of isotopes different?
They all have different numbers of neutrons
