Question

question 28 (1 point)
which of the following substances can act as a brønsted-lowry base?
\\(\ce{hclo4(aq)}
\\(\ce{hocl(aq)}
\\(\ce{h2o(l)}
\\(\ce{h3o+(aq)}
none of the above

Explanation:

Step1: Recall Brønsted - Lowry base definition

A Brønsted - Lowry base is a substance that can accept a proton ($\ce{H+}$).

Step2: Analyze each option

• For $\ce{HClO4(aq)}$: $\ce{HClO4}$ is a strong acid, it donates a proton ($\ce{HClO4 -> H+ + ClO4-}$), so it acts as a Brønsted - Lowry acid, not a base.
• For $\ce{HOCl(aq)}$: $\ce{HOCl}$ can donate a proton (to form $\ce{OCl-}$) and also can accept a proton? Wait, $\ce{HOCl}$ is mainly an acid (donates $\ce{H+}$ to form $\ce{OCl-}$), but let's check other options.
• For $\ce{H2O(l)}$: Water can accept a proton to form $\ce{H3O+}$ ($\ce{H2O + H+ -> H3O+}$) and also can donate a proton to form $\ce{OH-}$ ($\ce{H2O -> H+ + OH-}$). So water can act as a Brønsted - Lowry base (when it accepts a proton).
• For $\ce{H3O+(aq)}$: $\ce{H3O+}$ donates a proton to form $\ce{H2O}$ ($\ce{H3O+ -> H+ + H2O}$), so it acts as a Brønsted - Lowry acid.

Answer:

$\ce{H2O(l)}$ (the option with $\ce{H2O(l)}$)