Which of the following are arrhenius bases?
a) ch3oh
b) ch3cooh
c) hoh
d) h2nnh2

                  H₂O

Explanation:

                      According to Arrhenius Concept of Acid and Base, "Acid is any specie which when dissolved in water ionizes to produce H⁺ ions".

Examples:

                                  HCl    →    H⁺  +  Cl⁻

                                  H₂SO₄    →    2 H⁺  +  SO₄²⁻

While, "Bases are those species which when dissolved in water produces Hydroxyl Ions (OH⁻)".

Examples:

                                  NaOH    →  Na⁺  +  OH⁻

                                  Mg(OH)₂    →     Mg²⁺  +  2 OH⁻

Given Options:

CH₃OH:

             Methanol when dissolved in water does not dissociate as follow,

                                    CH₃OH     →     H₃C⁺  +  OH⁻

Hence, it does not behave as Arrhenius Base.

CH₃COOH:

                  Acetic acid when dissolved in water produces H⁺ ions and Acetate ions i.e.

                                 CH₃COOH    →    CH₃COO⁻  +  H⁺

Therefore, it can act as Arrhenius Acid instead of Arrhenius Base.

H₂O:

        Water when dissolved in water dissociates as,

                                                  H₂O    →    H⁺  +  OH⁻

As it is producing both H⁺ and OH⁻ ions therefore, it can act as both Arrhenius Base and Arrhenius Acid.

H₂NNH₂:

              Hydrazine when dissolved in water can neither produce OH⁻ ions nor H⁺ ions hence, it is neither Arrhenius Base nor Arrhenius Acid,

considering the question as per the attachment

here we can see that the radon nuclide has 222 as the atomic mass number and 86 as the atomic number.

when it undergoes nuclear fission it gives polonium which has atomic mass number as 218 and atomic number will be 84 along with a helium nucleus which has 4 atomic mass number and 2 as its atomic number.

222 = 218 + 4 (atomic mass number)

86 = ? + 2; therefore ? = 86-2 = 84.

the atomic mass number of polonium will be 84.