Unit: 1 - Atomic structure Flashcards
(21 cards)
What are the three subatomic particles in an atom and their charges?
Protons (+1), Neutrons (0), Electrons (-1)
Where are protons, neutrons, and electrons located in an atom?
Protons and neutrons are in the nucleus, while electrons orbit the nucleus in energy levels (shells)
What is the difference between the atomic number and the mass number?
The atomic number is the number of protons, while the mass number is the total number of protons and neutrons.
What do elements in the same group have in common?
They have the same number of valence (outer shell) electrons
What do elements in the same period have in common?
They have the same number of electron shells
Which side of the periodic table contains metals, and which side contains nonmetals?
Metals are on the left and center; nonmetals are on the right.
What is the maximum number of electrons in the first, second, and third shells?
First shell: 2, Second shell: 8, Third shell: 18
How are electrons arranged in an atom of sodium (atomic number 11)?
2, 8, 1
What happens to the electron arrangement of an atom when it forms a positive ion?
It loses electrons from its outer shell
What is the valency of an element in Group 1, and why?
Valency is 1 because it has one electron in its outer shell, which it tends to lose.
How does the valency of elements in Groups 1–17 change across the table?
Valency increases from 1 in Group 1 to 4 in Group 14, then decreases to 1 in Group 17
What is the valency of oxygen, and what kind of ion does it form?
Valency is 2, and it forms O²⁻ ions by gaining 2 electrons.
What is the number of neutrons in C^14’6(^ means superscript, ‘ sub script)?
Neutrons=A−Z=14−6=8.
What is an isotope?
Atoms of the same element with the same number of protons but different numbers of neutrons.
Give an example of two isotopes of hydrogen.
hydrogen-1 ^1H. and deuterium(^2H)
Do isotopes of the same element have the same chemical properties?
Yes, because they have the same electron arrangement
What are groups in the periodic table?
groups are columns in the periodic table containing elements with the same number of outer electrons, indicated by the group number
What is the mass of the particles?
protons and neutrons have an approximate mass of one atomic mass unit and electrons, in comparison, have virtually no mass
What are isotopes?
isotopes are defined as atoms with the same atomic number but different mass numbers, or as atoms with the same number of protons but different numbers of neutrons
Do most elements have isotopes?
most elements have two or more isotopes
How do we compute the average atomic mass of each isotope?
the average atomic mass has been calculated for each element using the mass and proportion of each isotope present. These values are known as relative atomic masses.
