Question

Question 7 1 pts Equal volumes of 0.50 M HBr and 0.50 M NH3 are mixed together. The resulting solution can be best described as: a buffer weakly basic weakly acidic. O neutral

Answer 1

Here the HBr is a strong acid and NH3 is a weak base , so the solution is a strong acid - weak base solution.

We know that to complete a acid-base reaction a equal mole of acid and base are needed. Here we see that an equal volume and an equal concentration of HBr and NH3 are react so we say that an equal mole of acid and bas are reacts. So after equivalent point no acid or base are left in the solution. So no buffer solution will be produce.

So to make the solution be neutral a more amout of weak base( same concentration) are needed to neutralize the strong acid.

But after the complete reaction a strong conjugate acid(NH4+) will be produce in the solution which will dissociate in aqueous solution and produce H+ ions . And presence of these H+ ion in solution make the solution be acidic.

So the correct option is : weakly acidic.

Thank You.