Which molecule is amphoteric?

a) nh4+

b )h2o

c )h2co3−

d )h2so4

B )

Explanation:- According to the Bronsted Lowry conjugate acid-base theory, an acid is defined as a substance which donates protons and a base is defined as a substance which accepts protons.

Amphoteric substances are substances which can act as both acids and bases and thus can accept and donate ions.

Here water acts as an acid as it donates ions.

Here water acts as a base as it accepts ions.

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.  

bcde is the incorrect answer it is a