A 30.0-mL sample of an unknown strong base is neutralized after the addition of 12.0 mL of a 0.150 M HNO3 solution. If the unknown base concentration is 0.0300 M, give some possible identities for the unknown base.

The question is incomplete, here is the complete question:

A 30.0-mL sample of an unknown strong base is neutralized after the addition of 12.0 mL of a 0.150 M HNO₃ solution. If the unknown base concentration is 0.0300 M, give some possible identities for the unknown base.  (Select all that apply)

A.)  Ca(OH)₂

B.)  LiOH

C.)  Sr(OH)₂

D.)  Al(OH)₃

E.)  NaOH

F.)  Ba(OH)₂

The unknown base could be

Explanation:

To calculate the number of moles for given molarity of solution, we use the equation:

       .......(1)

Molarity of solution = 0.150 M

Volume of solution = 12.0 mL

Putting values in equation 1, we get:

Molarity of solution = 0.0300 M

Volume of solution = 30.0 mL

Putting values in equation 1, we get:

Mole ratio of acid and base is calculated as:

Number of = 2 × number of ions

So, the unknown base is diprotic in nature.

Hence, the unknown base could be

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e