Atomic Theory Sample exam questions Flashcards
Define atomic orbital
Region of space around the nucleus where electrons are most likely to be found
Define first ionisation energy
The minimum energy required to remove most loosely bound electron from a neutral gaseous element in its ground state
Explain general increase in first ionisation energy across a period
- Increases across
- Decreasing atomic radius
- Increase in effective nuclear charge
- Screening effect remains the same
Define Atomic number
Number of protons in the nucleus of an atom
Define atomic mass
Number of protons and neutrons in the nucleus of an atom
Define Relative atomic mass
The average mass of an atom compared to 1/12th the mass of the carbon 12 isotope
Define electronegativity
The measure of the attraction that an atom has for the shared pair of an electron in a covalent bond
Describe how electronegativity values can be used to predict the type of bonds that occur between a pair of atoms
<0.4= pure covalent bond
>0.4 but <1.7=polar covalent bond
>1.7= ionic bond
explain the trend of atomic radius down the group
- Increases
- nuclear charge increases
- screening effect increases
explain why alkali metals are so reactive
- Group one
- 1 electron in its outer energy level
- it loses that one electron to follow the octet rule
Explain why alkali metals become more reactive down the group
- atomic radius increases down the group
Explain why bromine is less reactive than chlorine
- The electronegativity of Bromine is smaller
- The atomic radius is larger than chlorine
Explain why neon is chemically inert
8 electrons in its outside shell
How is an ionic bond formed between a pair of atoms
- Electrons are transferred to form a positive ion
- To form a negative ion
How is a double covalent bond formed between a pair of atoms
The sharing of 2 pairs of electrons
transition metal
one that forms an ion with an incomplete d-subshell
Give 2 characteristic properties of transition metals
variable valency
acts as a catalyst
what is a crystal
solid with a repeating pattern of atoms
Describe the bonding in a metallic crystal
positive ions with valence electrons being shared
would you expect nickel to be a good electrical conductor, why?
yes
electrons are free to move