15 Facts on HBr + Ca(OH)2: What, How To Balance & FAQs

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Calcium hydroxide and hydrobromic acid are inorganic compounds with chemical formulas, Ca(OH)2  & HBr, respectively. Let us explore more about Ca(OH)2 and HBr.

Ca(OH)2 is a colorless crystal or white powder having a polymeric structure. HBr is a colorless or faint yellow liquid and a strong mineral acid.

This article describes the various reactions of Ca(OH)2  + HBr-like products formed, redox reactions, reversible reactions, conjugate pairs, buffer solution, etc.

What is the product of HBr and Ca(OH)2?

Calcium bromide (CaBr2) and water (H2O) are formed when Ca(OH)2 and HBr reacts.

      HBr + Ca(OH)2    —>   CaBr2 + H2O.

What type of reaction is HBr and Ca(OH)2?

HBr +Ca(OH)2 is an acid-base reaction, also known as a neutralization reaction, in which a strong acid neutralizes a strong base to form salt and water.

How to balance HBr and Ca(OH)2?

The equation for the reaction between HBr and Ca(OH)2 is balanced using the following steps.

  • The general equation is HBr +Ca(OH)2 —> CaBr2 + H2O.
  • Calculate the number of moles on each element in both the reactant and product sides.
ElementsReactantsProducts
Ca11
Br12
O21
H32
Table showing the number of reactants and products in each element.
  • The number of moles of an element in the reactant and product sides is not equal.
  • Thus, the number of moles of Br on the reactant side is multiplied by 2.
  • The number of moles of O on the product side is multiplied by 2.
  • So, this eventually makes the H elements equal.
  • 2HBr +  Ca(OH)2   —>  CaBr2 + 2H2O.

HBr + Ca(OH)2  titration

The acid-base titration between  HBr and Ca(OH)2 can be performed in the following way –

Apparatus

Burette, burette holder, conical flask, pipette, stirrer, beakers, distilled water, volumetric flask, wash bottle.

Indicator

Phenolphthalein is used as an indicator for acid-base titrations to indicate the endpoint of the titration.

Procedure

  • 0.1 N Ca(OH)2 is taken in a clean burette.
  • 10 ml of HBr is pipette out into a conical flask.
  • Add 2-3 drops of phenolphthalein indicator into a conical flask.
  • Add Ca(OH)2 dropwise from the burette till pale pink color appears.
  • Repeat this for 3 readings.
  • Using the final value calculate the amount of Ca(OH)2 required to neutralize HBr by the formula M1V1=M2V2.

HBr + Ca(OH)2  net ionic reaction.

  • The net ionic reaction is H+(aq) +OH–(aq)  —> H2O(l).
  • The net ionic reaction is determined by separating all the elements in their ionic form as below :
  • 2H+(aq) + 2Br-1(aq) +Ca2+(aq) + 2OH–(aq) —> Ca2+(aq)  +2Br–(aq) + 2H2O(l).
  • The ions in both the sides of the anion and the cation are removed as in the below equation.
  • 2H+(aq) + 2OH–(aq)   —> 2H2O(l).
  • The final equation involves the ions that are present in the reaction.
  • By arranging the equation 2H+ (aq) + 2OH–(aq)  —> 2H2O in the simplified form
  • H+(aq) +OH– (aq)  —> H2O(l).

HBr +Ca(OH)2 conjugate pairs

  • Br– acts as a conjugate base, as HBr is a strong acid.
  • Conjugating acid is Ca2+a weak acid from a strong base.

HBr + Ca(OH)2 intermolecular forces

  • HBr has a dipole-dipole intermolecular force between them.
  • Ca(OH)2 has a strong electrostatic force of attraction between anion and cation.

HBr + Ca(OH)2 reaction enthalpy

The reaction enthalpy between HBr and Ca(OH)2 is negative.

Is HBr + Ca(OH)2  a buffer solution?

HBr + Ca(OH)2 is not a buffer solution. HBr is not a weak acid, and a salt is formed in the reaction.

Is HBr + Ca(OH)2 a complete reaction?

HBr + Ca(OH)2  is a complete reaction, thus forming a stable product.

Is HBr +Ca(OH)2 an exothermic reaction?

HBr + Ca(OH)2 is an exothermic reaction, releasing heat as the reaction enthalpy is negative.

Is HBr + Ca (OH)2  a redox reaction?

HBr + Ca(OH)2  is not a redox reaction. The oxidation states do not change in the reaction.

 Is HBr + Ca(OH)2 a precipitate reaction?

HBr + Ca(OH)2 is a precipitation reaction as CaBr2 is formed as a product.

Is HBr + Ca(OH)2 a displacement reaction?

HBr + Ca(OH)2 is a double displacement reaction because anions and cations get displaced to form salt and water.

hbr caoh2 2
Double displacement reaction.

Conclusion

Ca(OH)2 is widely used in the paper industry and the preparation of ammonia. HBr is used as a bromine source in industries.CaBr2 is used in photography and is an excellent wood preservative.