Question

Magnesium bromide is a salt of ____.
A. Oxyacid
B. Binary acid
C. Strong acid
D. Weak base

Answer 1

Magnesium bromide is a chemical compound composed of magnesium and bromine atoms and its chemical formula is $MgB{r_2}$. It is white, deliquescent and a water-soluble compound which can be naturally found in small quantities in some minerals like carnallite and bischofite.

Complete answer:
Let us first have a look on the meaning of each term given in the options:
Oxyacid: It is a ternary acid which contains oxygen, hydrogen and at least one other element. In an oxyacid minimum one hydrogen atom must be bonded to the oxygen atom in order to produce protons and form anion i.e., conjugate base of the acid. The general structure of an oxyacid is represented as $X - O - H$.
Binary acid: These are the certain molecular acids in which a hydrogen atom combines with a non-metallic element to form compounds which have $H - X$ type molecular structure. The acidic strength of binary acids depends on its bond strength i.e., the weaker the bond, the stronger the acidity will be. Some examples of binary acids are $HCl$, $HBr$, etc.
Strong acid: It is an acid which completely ionizes in an aqueous solution. These acids always lose a proton when dissolved in water and the pH of these acids lie between $1$ and $3$. Some of the examples of strong acid are ${H_2}S{O_4}$, $HBr$, etc.
Weak base: It is a type of base which does not dissociate completely on dissolution in water due to which the resulting solution consists of only a small proportion of hydroxide ions and a large proportion of undissociated base molecules. Examples of a weak base are $N{H_3}$, $N{H_4}OH$, etc.
Now, the formation of magnesium bromide takes place as follows:
When magnesium oxide reacts with hydrobromic acid, then the formation of magnesium bromide takes place along with the removal of water. The reaction proceeds as follows:
$MgO + 2HBr \to MgB{r_2} + {H_2}O$
Hence, magnesium bromide is a salt of a binary acid.
Therefore, option (B) is the correct answer.

Note:
It is important to note that although hydrogen bromide is a strong acid but primarily in acids, we first check the composition and then its strength. The composition of hydrobromic acid resembles that of binary acids. Hence, the answer for this question is binary acid instead of a strong acid.