the periodic table of the elements

123456789
Across
  1. 1. an element that forms basic gas on combining with hydrogen
  2. 4. the elements in the 17th group in the periodic table
  3. 7. the modern periodic table was created by ___.
  4. 8. the most electronegative element in the periodic table
  5. 9. an element that burns brick-red
Down
  1. 1. these elements do not react with any element or compound
  2. 2. an element that reacts violently with cold water and can be cut with a knife
  3. 3. the number of shells in an atom increases down a ____.
  4. 5. an amphoteric element that belongs to the 13th group of the periodic table
  5. 6. the electronegativity of elements increases across a _____.