Mendeleev made an early periodic table. In the modern periodic table, elements are in order of atomic number in periods and groups. Electronic configurations model how electrons are arranged in atoms.
What order did Mendeleev place the elements in to form his first periodic table?
Number of electrons
How are the elements arranged in the modern periodic table?
Increasing atomic number
Increasing mass number
Increasing electron shells
Why did Mendeleev leave gaps in his periodic table?
Because some elements took up two spaces
Because the mass numbers were wrong
Because there were elements still to be discovered
What is the electron arrangement of an element with an atomic number of 16?
Which statement about the elements in the modern periodic table is correct?
Most elements are metals and they are found on the right
Most elements are metals and they are found on the left and in the middle
Most elements are non-metals and they are found on the right
What name is given to the horizontal rows in the periodic table?
Where is the element with the electron arrangement: 220.127.116.11 found in the periodic table?
The element is found in period 4 and group 2
The element is found in period 2 and group 2
The element is found in period 4 and group 4
Which part of the atomic structure has most effect on the chemical properties and reactions of an element?
The proton neutron ratio
The outer electron shell
Which atom will have similar chemical properties to the atom with:
Atomic number = 12
Mass number = 24
Electronic configuration 2.8.2
The atom with: atomic number = 11 mass number = 24 electronic configuration 2.8.1
The atom with: atomic number = 6 mass number = 12 electronic configuration 2.4
The atom with: atomic number = 20 mass number = 40 electronic configuration 18.104.22.168
What changes in atomic structure occur as you move from left to right along the horizontal rows in the periodic table?
The number of protons in the nucleus increases by one
The mass number increases by one
The number of electrons shells increases by one