Periodicity Flashcards
What is meant by periodicity?
The repeating pattern of physical and chemical properties that is seen at regular intervals in the periodic table
What is Atomic Radii?
The distance from the center of the nucleus to the outermost electron
What are 2 factors that determine melting points?
- The structure if the element
2. The type of attractive forces holding the atoms together
What are alkali metals and why are they called that?
Li,Na,K- because they can react with water to form metal hydroxide and hydrogen gas
-also react with halogens to give salts
Halogen reactivity?
A more reactive halogen displaces less reactive halogen from one of its compounds
F>Cl>Br>I
What is the definition of a Transition Metal?
An element having an incomplete d-shell in one or more of their oxidation states
What is a ligand?
Any atom, molecule or ion which can donate a pair of electrons to a metal ion to form coordinate bonds when complex ion is formed
What is a complex ion?
Consists of a central metal ion surrounded by ions or molecules known as ligands
What is a coordination number?
The number of lone pairs bonded to the metal ion
Why do we see color-transition metals?
D-orbitals are split into two distinct levels, the energy differernce corresponds to the wavelength in the visible region of spectrum-when the light falls on the complex, energy of the particular wavelength is absorbed and electrons are excited from lower to higher level-color is complementary to wave lengths absorbed
What are examples of transition catalysts?
Iron in Haber process
Vanadium Oxide in Contact Process
Nickel in Hydrogenation reactions
Manganese(iv) Oxide with Hydrogen peroxide
What is electronegativity?
The ability of an atom to pull electron density from a covalent bond to itself
