15 Facts on HCl + NH4Br: What, How To Balance & FAQs

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Hydrochloric acid is a solution of gases (H2 and Cl2) in water.  Ammonium Bromide is a salt of HBr and has a saline taste. Let us now see how HCl + NH4Br reacts with each other.

When hydrogen bromide directly acts on ammonia, NH4Br formation takes place. HCl or hydrogen chloride is a colorless gas that has a very strong odor. NH4Br is a very weak acid in comparison with HCl (i,e strong acid).

Now in this article, we will discuss the HCl + NH4Br reaction, net ionic equations, reaction type, conjugate pairs, enthalpy, etc in detail.

What is the product of HCl and NH4Br

Hydrobromic acid (HBr) and Salammoniac (NH4Cl) are the products formed by the reaction of Ammonium Bromide(NH4Br) and Hydrogen Chloride(HCl). 

NH4Br + HCl → NH4Cl + HBr

What type of reaction is HCl +NH4Br

The HCl + NH4Br reaction is a double-displacement reaction or metathesis type of reaction.

NH4Br + HCl → NH4Cl + HBr

Double displacment reaction 1 1
Double – displacement reaction

How to balance HCl+ NH4Br

The unbalanced equation for the reaction of HCl + NH4Br is written as-

NH4Br + HCl → NH4Cl + HBr

To balance the above equation we use the following steps-

  • First, assign different variables for each of the compounds on both sides(i.e products and reactants).
  • a NH4Br + b HCl → c NH4Cl + d HBr
  •  Several different equations are formed for each element, which represents the total number of atoms present.
  • N; 1a =1c, H; 4a+1b= 4c +1d, Br; 1a=1d, Cl;1b=1c
  • Now, by using the substitution or elimination method to solve the above equation for each variable, then we get-
  • a=1(NH4Br), b=1HCl, c=1NH4Cl, d=1HBr
  • Now count the number on both sides, we get-
ELEMENTSLHSRHS
N11
H55
Br11
Cl11
Number of atoms on both the sides
  • Thus the balanced equation is,
  • NH4Br + HCl → NH4Cl + HBr

HCl + NH4Br titration

Titration of HCl and NH4Br is not possible. As both the medium are acidic because the change in pH is not abrupt enough at either equivalence point to permit estimation with visual indicators.

HCl + NH4Br net ionic equation

The net ionic equation for the reaction of HCl + NH4Br is-

NH4Br (s) + H+(aq) + Cl–(aq)   =    NH4Cl(s) + H+(aq) + Br– (aq)

To get a net ionic equation following steps are used-

  • First, write the complete inning equation as follows-
  • NH4+(s)  + Br–(s)  + H+(aq) + Cl–(aq)  =  NH4+(s) + Cl–(s) +  H+(aq) + Br– (aq)
  • In this reaction H+ ion is a spectator ion, so it gets canceled from both sides.
  • After, removing the H+ ion from both the product and reactant side the remaining equation is the net ionic equation of the reaction.
  • Thus, the net ionic equation of the HCl + NH4Br reaction is –
  • NH4Br (s) + Cl–(aq)   =    NH4Cl(s) + Br– (aq)

HCl + NH4Br conjugate pairs

In the reaction HCL +NH4Br the conjugate acid-base pairs are as follows-

  • Conjugate base of HCl = Cl –
  • Conjuagte acid of HCl = H3O+
  • Conjugate base of NH4Br = NH4+
  • Conjugate acid of NH4Br= Br-

HCl and NH4Br intermolecular forces

The reaction between HCl and NH4Br has the following intermolecular forces-

  • In NH4Br, the ionic forces of attraction are present.
  • The molecule of HBr has dipole-dipole forces as it is a polar molecule. There are also dispersion forces present. Among both of the forces dipole-dipole interactions, forces are stronger.

HCl + NH4Br reaction enthalpy

The reaction enthalpy of HCl + NH4Br is -28.1 kJ/mol. It is calculated as follows-

CompoundEnthalpy of formation KJ/mol
NH4Br-270.8
HCl-92.2
NH4Cl-314.4
HBr-20.2
Enthalpy of formation
  • The total reaction enthalpy = ∑ ∆H0f (products) – ∑ ∆H0f (reactant)
  • ∆H = (-314.4) + (-20.2) – (-270.8) + (-92.2) kJ/mol
  • ∆H = -28.1 kJ/mol

Is HCl +NH4Br a buffer solution

When HCl and NH4Br are mixed, it does not form a buffer solution . As for the buffer solution, a weak acid and its weak salt are mixed but here, hydrochloride acid is present which is a very strong acid.

Is HCl + NH4Br a complete reaction

The reaction HCl +NH4Br is a complete reaction as HBr and Salammoniac are the products formed during the reaction and no further products are formed or the reaction cannot be carried on further.

Is HCl + NH4Br an exothermic or endothermic reaction

HCl + NH4Br is an exothermic reaction as the total enthalpy of formation is negative (-28.1 kJ/mol).

Is HCl + NH4Br a redox reaction

The reaction HCl + NH4Br is not a type of redox reaction, as there is no change in the oxidation number of any element on the both (product and reactant) sides takes place.

Is HCl + NH4Br a precipitation reaction

HCl + NH4Br is not a precipitation reaction as the products (ammonium chloride and hydrogen bromide) formed during this reaction are soluble and no precipitate is formed.

Is HCl + NH4Br reversible or irreversible reaction

HCl+ NH4Br is a reversible reaction as all the products formed in the reaction are soluble and no gas is evolved during the reaction which makes it convertible.

Is HCl + NH4Br displacement reaction

The HCl + NH4Br reaction is a displacement reaction as in this reaction, Br of NH4Br is displaced by Cl; and Cl from HCl is displaced by Br to form the respective products.

NH4Br + HCl → NH4Cl + HBr

Conclusion

Ammonium bromide is a white color powder, with 97.94 g/mol of molar mass. When it reacts with HCl gives ammonium chloride which is used in fertilizers and food additives etc. Hydrobromic acid (HBr) is generally used as a source in bromine manufacturing industries.