Hydrogen gas
Calcium + Water. In the following demonstration, a chunk of calcium metal is dropped into a beaker of distilled water. After a second or so, the calcium metal begins to bubble vigorously as it reacts with the water, producing hydrogen gas, and a cloudy white precipitate of calcium hydroxide.
Answer:
Sorry I’m not rlly sure but maybe the 2nd or the last
Explanation:
Answer to this is O-atom.
Explanation: The Bronsted acid-base theory is the backbone of chemistry. This theory focuses mainly on acids and bases acting as proton donors or proton acceptors.
where 
is the Lewis Acid and 
is the Lewis Base and 
is the Covalent Bond.
Reaction of dissociation of 
in 
is given as:
In this reaction O-atom has lone pair in water and therefore it accepts the proton from 
forming a Lewis Base.
Hey :)
The answer is B) Nitrogen, which has an electronegativity of 3.04
Hope this helps!
