If the two members of a Dobereiner triad are phosphorus and antimony, the third member of this triad is –
Which scientist came up with the concept of a periodic table that included all of the known elements?
Dmitri Mendeleev is credited with designing the modern periodic table. Joseph Priestly and Antoine Lavoisier were both chemists. Albert Einstein developed theories on photoelectric effect
The noble gases are unreactive because
Which shows variable valency–
If the valene shell electronic configuration for an element is ns2np5, this element will belong to the group of –
Which of the following elements does not lose an electron easily?
F has atendency to gain an electron.
Which one of the following elements exhibit maximum number of valence electrons?
P is in group 5 and has 5 valence electron.Number of valence electrons in Na, Al and Si are 1, 3 and 4.
Which is a metalloid?
As you move down the group, the alkali metals become
View Answer & Solution