The Periodic Table

In 1913, ___ slightly changed Mendeleev's table to make it even better.

How many groups are on the periodic table?

In the 1800's, the modern periodic table was first published by __.

The element in group 16 period 2 is ___.

Which of the following elements is in the 1st period?

Horizontal rows on the periodic table are called __.

The element in group 5 period 7 is ___.

The element in group 14 period 5 is __.

Which of these elements did Mendeleev predict, even though it had not been discovered?

What are vertical columns called on the periodic table?

The element in group 1 period 18 is ___.

Which of the following element is in group 13?

How many periods are on the periodic table?

The element in group 6 period 6 is ___.

The element in period 3 group 2 is ___.