unit 1 KA1 - periodicity

Question 1

how are elements arranged in the periodic table

Answer 1

in order of increasing atomic number

Question 2

what does the periodic table allow chemists to make predictions on

Answer 2

• physical properties

- chemical behavior

Question 3

what are groups

Answer 3

vertical columns within the table contain elements with similar chemical properties resulting from a common number of electrons in the outer shell

Question 4

what are periods

Answer 4

rows of elements arranged with increasing atomic number, demonstrating an increasing number of outer electrons and a move from metallic to non-metallic characteristics

Question 5

what is meant by covalent radius

Answer 5

the measure of the size of an atom. the trends in covalent radius across periods and down groups can be explained in terms of the number of occupied shells and the nuclear charge

Question 6

what is the first ionization energy

Answer 6

the first ionization energy is the energy required to remove one mole of electrons from one mole of gaseous atoms.

Question 7

what are the second and subsequent ionization energies

Answer 7

they are the energies that refer to the energies required to remove further moles of electrons

Question 8

how can the trend in ionization energies be explained

Answer 8

in terms of atomic size, nuclear charge and the screening effect due to inner shell electrons

Question 9

is it true that atoms of different elements have different attractions for bonding electrons

Answer 9

yes

Question 10

what is electronegativity

Answer 10

the measure of the attraction an atom involved in a bond has for the electrons of the bond

Question 11

how can the trends in electronegativity across periods and down groups be rationalized

Answer 11

in terms of covalent radius, nuclear charge and the screening effect due to inner shell electrons