How many valance electrons are in group 2A?
How many valence electrons?
How many valence electrons do halogens have?
What group of elements has a "full octet"?
What is the most reactive group of elements?
Which is more reactive?
Helium or Francium
How many valence electrons in Group IA?
How many valence electrons has Mg?
How many valence electrons in Group VIIA?
What group is this element in?
1s2 2s2
Створюйте онлайн-тести
для контролю знань і залучення учнів
до активної роботи у класі та вдома