Atomic Structure and the Periodic Table - Detailed Flashcards
(21 cards)
Q: What are the three subatomic particles in an atom?
Protons
Neutrons
Electrons
Q: What are the charges and locations of the subatomic particles?
- Protons: Positive charge (+1), located in the nucleus
- Neutrons: No charge (0), located in the nucleus
- Electrons: Negative charge (-1), orbiting the nucleus in shells
Q: What determines the atomic number of an element?
The number of protons in the nucleus
Also equals the number of electrons in a neutral atom
Q: What is the mass number of an atom?
The total number of protons and neutrons in the nucleus
Mass number = protons + neutrons
Q: What is an ion?
An atom or molecule with a net electric charge due to the loss or gain of electrons
Cation: positively charged ion (loss of electrons)
Anion: negatively charged ion (gain of electrons)
Q: How does an atom become a positive ion (cation)?
By losing one or more electrons
Results in more protons than electrons
Q: How does an atom become a negative ion (anion)?
By gaining one or more electrons
Results in more electrons than protons
Q: What information does the nuclear symbol of an element provide?
The atomic number (number of protons)
The mass number (protons + neutrons)
The chemical symbol of the element
Q: How can you calculate the number of neutrons in an atom?
Number of neutrons = mass number - atomic number
Q: Why do atoms form ions?
To achieve a full outer electron shell
This makes them more stable
Q: What is the definition of an isotope?
An isotope is an atom of the same element that has the same number of protons but a different number of neutrons.
This difference in neutrons results in different mass numbers.
Q: What is the difference between the mass number and atomic number?
The atomic number is the number of protons in the nucleus, which defines the element.
The mass number is the total number of protons and neutrons in the nucleus.
Q: How do you find the number of neutrons in an atom?
Number of neutrons = mass number - atomic number.
Example: In chlorine-35, the mass number is 35, and the atomic number is 17. So, neutrons = 35 - 17 = 18.
Q: What is relative atomic mass (RAM)?
Relative atomic mass is the weighted average mass of the atoms of an element, taking into account the mass and relative abundance of each isotope.
It is usually calculated from the isotope masses and their natural abundances.
Q: How do isotopes affect the relative atomic mass of an element?
Isotopes contribute to the relative atomic mass depending on their mass and abundance.
Heavier isotopes with higher abundance increase the relative atomic mass.
Q: Why do isotopes of the same element have the same chemical properties?
Because isotopes have the same number of electrons in their outer shells, which determines chemical reactions and bonding.
Q: How can you calculate the relative atomic mass of an element with two isotopes?
Relative atomic mass = (mass of isotope 1 × abundance of isotope 1) + (mass of isotope 2 × abundance of isotope 2)
Then divide by total abundance (usually 100).
Q: What are the units for relative atomic mass?
Relative atomic mass has no units because it is a ratio comparing the mass of an atom to 1/12th the mass of a carbon-12 atom.
Q: What is an example of an isotope with a practical use?
Carbon-14 is used in carbon dating to estimate the age of ancient organic materials.
Other isotopes like Iodine-131 are used in medical treatments like radiation therapy.
Q: What is the significance of the atomic mass unit (amu)?
The atomic mass unit (amu) is used to express the mass of atomic particles.
1 amu is defined as 1/12th the mass of a carbon-12 atom, which is approximately equal to the mass of a proton or neutron.
