HISTORY OFTHE MODERN PERIODIC TABLE OF ELEMENTS

Question 1

the organized array of all
the chemical elements in order of increasing atomic
number—i.e., the total number of protons in the atomic
nucleus

Answer 1

PERIODIC TABLE

Question 2

WHEN ELEMENTS ARE ARRANGED IN ORDER OF
INCREASING ATOMIC NUMBER, THERE IS A PERIODIC
PATTERN IN THEIR PHYSICAL AND CHEMICAL PROPERTIES

Answer 2

PERIODIC LAW

Question 3

• In 1829, he classified some elements into groups
  of three, which he called triads. The elements in
  a triad had similar chemical properties and
  orderly physical properties
• MODEL OF TRIADS

Answer 3

JOHANN DOBEREINER

Question 4

• In 1863, he suggested that elements
  be arranged in “octaves” because he
  noticed (after arranging the elements
  in order of increasing atomic mass) that
  certain properties repeated every 8th
  element
• LAW OF OCTAVES

Answer 4

JOHN NEWLANDS

Question 5

• (1836-1907) published a periodic table of the elements by its organized increasing atomic mass
• This type of a
  repeating pattern is called “periodic”
• FATHER OF PERIODIC TABLE

Answer 5

DMITRI MENDELEEV

Question 6

In 1913, through his work with Xrays, he determined the actual
nuclear charge (atomic number) of
the elements. He rearranged the
elements in order of increasing
atomic number

Answer 6

HENRY MOSELEY

Question 7

After co-discovering 10 new elements, in 1994
he moved 14 elements out of the main body
of the periodic table to their current location
below Lanthanide series. These became
known as the Actinide series

Answer 7

GLENN T. SEABORG

Question 8

is the world authority on chemical
nomenclature, terminology (including the naming of
new elements in the periodic table)

Answer 8

International Union of Pure and Applied Chemistry
(IUPAC)

Question 9

horizontal rows of the periodic table are called

Answer 9

periods

Question 10

• elements in any _ of the periodic table have similar physical and chemical properties
• vertical columns of the periodic table are called

Answer 10

groups or families

Question 11

• very reactive, soft, malleable and ductile
• good conductors of heat and electricity

Answer 11

alkali metals

Question 12

• 2nd most reactive elements
• malleable, ductile and good conductors of heat and electricity but not as soft as alkali metals

Answer 12

alkaline earth metals

Question 13

• hard (with mercury as an exception)
• malleable, ductile and good conductors of electricity

Answer 13

transition metals

Question 14

• these elements are also called the rare-earth elements
• they are special series of elements but are also part of the transition block
• 2 series: lanthanides and actinides

Answer 14

inner transition metals

Question 14

• salt former
• exist in all 3 states of matter

Answer 14

halogens

Question 15

• stable gases
• non-reactive or inert elements

Answer 15

noble gases