In the following acid-base reaction, Cl- is the
HCI(g) + H2O(l) →H30+(aq) + Cl(aq)
acid
base
conjugate
base

conjugate base

Explanation:

The following equation is given in this question:

HCI(g) + H2O(l) → H30+(aq) + Cl-(aq)

In accordance to Brønsted–Lowry acid–base theory, an acid is a substance that loses an hydrogen ion (H+) or proton in an aqueous solution. This theory further indicated that the substance formed after an acid loses its hydrogen ion is called a CONJUGATE BASE.

In the above equation, HCl is the acid because it loses H+ while the substance formed after the loss of H+, which is Cl- is a conjugate base.

2h2o2--> 2h2o + o2

this reaction is of the spontaneous decomposition of hydrogen peroxide down into water and oxygen.

add 2 molecules of hydrogen peroxide and 2 molecules of water. since oxygen is naturally diatomic, the total number of atoms of each element is now the same on both sides of the equation so it is balanced.

this may not be entirely correct but let me know.