Trends in the Periodic Table Flashcards
What are trends?
Specific patterns found in the periodic table that illustrate different aspects of an element.
Why do these trends exist?
- Similar atomic structure of elements in their respective groups or periods, due to their arrangement in the periodic table.
- Because of the periodic nature of elements.
Why are trends important?
- Because they help predict the chemical and physical properties of the element.
- Trends are based on the periodic law.
What is atomic size?
The distance between the nucleus and the outermost electron.
What does the atomic size depend on?
- No. of energy levels
- Proton pulling power
Why does atomic size increase down a group?
Because an extra energy level is added, and this decreases over all attraction.
True or False: Atomic size increases left to right, across a period.
False.
Because a proton is added, e- is added in the same energy shell
Why is the size of cation less than neutral atom?
Because cation has more protons than electrons so effective nuclear charge increases, pulling the electrons closer.
Why is the size of anion greater than neutral atom?
Because anion has more electrons than protons, so effective nuclear charge and attraction decrease, increasing the size.
Why does the size of anions decrease across the period?
Although no. of electrons exceeds no. of protons, the electrons are added in the same shell, hence, increasing attraction.
What is ionization energy?
Ionization energy is the lowest possible energy value required to remove one electron from the outer shell of an atom.
How do Group 1 elements easily form ions?
Because they have low values of ionization energy.
Why do Group 18 elements have high values of ionization energy?
Because they have a complete octet, which accounts for their high stability and non-reactivity.
What is electronegativity?
Ability to attract electrons in a chemical bond
What is electronegativity measured in?
In Pauling scale
