What kind of elements in the periodic table did William Ramsay discover?
The inertness of noble gases means that they:
Noble gases are inert due to:
In chemical reactions, when atoms gain or lose electrons they form:
The number of valence electrons in the group A elements is determined by:
What type of elements lose electrons when they enter into chemical reactions?
What type of elements gain electrons when they enter into chemical reactions?
What is the maximum number of electrons that helium can have?
Under what category of elements does helium fall:
What is an exothermic chemical reaction?
What is an endothermic chemical reaction?
What reaction happens immediately after two substances are mixed?
What kind of change accompanies any chemical reaction?