Term 1 Atomic Structure and the Periodic Table Flashcards
Location, charge and relative mass of Proton
Location: Nucleus
Charge: +1
Relative Mass: 1 amu
Location, charge and relative mass of Neutron
Location: Nucleus
Charge: 0
Relative Mass: 1 amu
Location, charge and relative mass of Electron
Location: Orbiting nucleus in shells
Charge: -1
Relative Mass: ~1/1836 amu
What is the nucleus made up of
Protons and neutrons
Where is nucleus located
Center core of the atom
What is the overall charge of the nucleus
Positive
Overall charge of atom
An atom is electrically neutral as the total positive charge from protons equals the total negative charge from electrons.
Any imbalance results in an ion with a net positive or negative charge
What does the atomic number represent
Represents the number of protons in the nucleus of an atom.
What does the mass number represent
Sum of the number of protons and neutrons in the nucleus of an atom.
How can you find the number of protons
Equal to the atomic number
How can you find the number of electrons
In a neutral atom, the number of electrons is equal to the number of protons
How can you find the number of neutrons
Calculated by subtracting the atomic number from the mass number
What is the relationship between number of valence electrons and reactivity
Atoms with few valence electrons (alkali metals) tend to be more reactive because they have a strong tendency to gain, lose, or share electrons to achieve a stable electron configuration.
Atoms with a full valence shell (such as the noble gases) are generally unreactive because they already have a stable electron configuration and do not readily gain or lose electrons.
What do the columns on the periodic table tell us
Same number of valence electrons and they have similar properties
What do the periods on the periodic table tell us
Same number of electron shells
for anions which direction on the periodic table makes it more reactive
anions (negatively charged ions), reactivity tends to increase as you move up and to the left on the periodic table. This is because as you move up a group (column), the atomic radius decreases and the outermost electrons are held more tightly by the nucleus, making it harder for them to be gained or lost.
Additionally, as you move to the left across a period (row), the effective nuclear charge (the positive charge felt by the outer electrons) increases, making it easier to attract additional electrons
for cations which direction on the periodic table makes it more reactive
For cations (positively charged ions), reactivity generally increases as you move down and to the left on the periodic table. This is because as you move down a group (column), the atomic radius increases, allowing for easier loss of outer electrons. Additionally, as you move to the left across a period (row), the effective nuclear charge decreases, making it easier to lose electrons. So, cations towards the bottom and left of the periodic table are typically more reactive.
