Periodic Table Flashcards
Define periodic property
A physical or chemical property that is repeated in a regular pattern for elements when they are arranged according to their atomic number
Define period
Refer to the rows in the periodic table. Drone left to right in the table the elements change from metals to non metals
Define group
Refer to the columns in the periodic table. Elements in a given group bear many similar physical and chemical properties
What are the periodic properties
Atomic size or radius, ionization energy, electron affinity and electronegativity
Define atomic size or radius
A measure of the size of the atom. It is found by determining half of the separation distance between the nuclei of the two adjacent atoms
What are the trends of atomic size or radius
Increases down each group because he valence electrons occupy an energy level that is farther from the nucleus.
Decreases across a period because the positive charge in the nucleus increases across a period
Define ionization energy
The energy needed to remove the most loosely held electron from the atom
What are the trends of ionization energy
Decrease down a group
Increase across a period
Define electron affinity
A measure of energy change that occupies when an electron is added to the outer energy level of an atom to form a negative ion on anion
What are the trends or electron affinity
Decreases down a group
Increases across a period
Define electronegativity
Measure of and atoms ability to attract electrons in a chemical bond
Now recorded for noble gases because they do not usually participate in bonding
What are the trends of electronegativity
Increases across a period
Decreases down a period
What is the chemical reactivity of alkali metals
Increases as you go down the group Each metal gives a distinct colour flame in the flame test Relatively hard but hardness decreases as you go down the group Low density (some float on water)
What is alkali reactivity with water
Very reactive
Generates hydrogen gas and aqueous solution of metal hydroxide
What is alkali reactivity with oxygen
Very reactive with oxygen
Reacts with oxygen to form an oxide