Question

Complete and balance each of the following neutralization reactions: (a) ${\mathrm{HNO}}_3(aq)+\mathrm{Ba}(\mathrm{OH}{)}_2(aq)\to$ (b) ${\mathrm{H}}_2{\mathrm{SO}}_4(aq)+\mathrm{NaOH}(aq)\to$

Short answer

(a) $2{\text{HNO}}_3(aq)+{\text{Ba(OH)}}_2(aq)\to {\text{Ba(NO}}_3{)}_2(aq)+2{\text{H}}_2\text{O}(l)$. (b) ${\text{H}}_2{\text{SO}}_4(aq)+2\text{NaOH}(aq)\to {\text{Na}}_2{\text{SO}}_4(aq)+2{\text{H}}_2\text{O}(l)$.

Step-by-step solution

Identify the Reaction Type

The reactions given are neutralization reactions, which involve an acid and a base reacting to form water and a salt.

Determine Products for Reaction (a)

For the reaction ${\mathrm{HNO}}_3(aq)+{\mathrm{Ba}(\mathrm{OH})}_2(aq)\to$, the products are water ${\text{H}}_2\text{O}$ and the salt, which is formed from the nitrate ion $({\text{NO}}_3^{-})$ and barium $({\text{Ba}}^{2+})$. The salt is ${\text{Ba(NO}}_3{)}_2$.

Balance Reaction (a)

The unbalanced equation is ${\mathrm{HNO}}_3(aq)+{\mathrm{Ba}(\mathrm{OH})}_2(aq)\to \mathrm{Ba}({\mathrm{NO}}_3{)}_2(aq)+{\text{H}}_2\text{O}$. We need 2 molecules of ${\text{HNO}}_3$ to supply 2 nitrate ions for each ${\text{Ba}}^{2+}$. Thus, the balanced equation is $2{\text{HNO}}_3(aq)+{\text{Ba(OH)}}_2(aq)\to {\text{Ba(NO}}_3{)}_2(aq)+2{\text{H}}_2\text{O}(l)$.

Determine Products for Reaction (b)

For ${\mathrm{H}}_2{\mathrm{SO}}_4(aq)+\mathrm{NaOH}(aq)\to$, the products are water ${\text{H}}_2\text{O}$ and the salt ${\text{Na}}_2{\text{SO}}_4$. The sulfate ion $({\text{SO}}_4^{2-})$ combines with sodium $({\text{Na}}^{+})$.

Balance Reaction (b)

The initial unbalanced equation is ${\mathrm{H}}_2{\mathrm{SO}}_4(aq)+\mathrm{NaOH}(aq)\to {\mathrm{Na}}_{2}ext{SO}_4(aq)+{\text{H}}_2\text{O}(l)$. To balance, we need 2 $\text{NaOH}$ to supply two ${\text{Na}}^{+}$ ions needed for ${\text{Na}}_2{\text{SO}}_4$. So, the balanced equation is ${\mathrm{H}}_{2}ext{SO}_4(aq)+2\text{NaOH}(aq)\to {\text{Na}}_2{\text{SO}}_4(aq)+2{\text{H}}_2\text{O}(l)$.

Verify Balancing

Check atom counts on both sides of each balanced equation. Both balanced equations should have the same number of each type of atom on both the reactant and product sides.

Key concepts

Balancing Chemical Equations

Balancing chemical equations is a crucial skill in chemistry that ensures that the same number of each type of atom appears on both sides of the equation. This principle is derived from the law of conservation of mass, which states that mass cannot be created or destroyed in a chemical reaction. When balancing equations, you adjust the coefficients in front of compounds or elements to make sure everything lines up. For instance, in the reaction $$2{\text{HNO}}_3(aq)+{\text{Ba(OH)}}_2(aq)\to {\text{Ba(NO}}_3{)}_2(aq)+2{\text{H}}_2\text{O}(l)$$we made sure there are exactly:

• Four hydrogen atoms (from two water molecules)
• Two nitrogen atoms
• Six oxygen atoms (in addition to the ones in water molecules)
• One barium atom on each side

It’s like solving a puzzle, ensuring every atom is accounted for without changing the actual molecules or breaking them apart.Balancing reactions might seem tricky at first, but with practice, it becomes much more intuitive!

Acid-Base Reactions

Acid-base reactions, such as those found in neutralization reactions, occur when an acid reacts with a base to produce a salt and water. In these reactions:

• An acid donates a proton ($ext{H}^{+}$) to the base.
• Often, acids have a sour taste and turn blue litmus paper red, while bases feel slippery to touch and turn red litmus paper blue.
• The reaction typically results in a pH value that is closer to 7 as the acid and base effectively cancel each other out.

An example can be taken from the neutralization of $ext{H}_{2}ext{SO}_4$ with $extNaOH$: The sulfuric acid ($ext{H}_{2}ext{SO}_4$) reacts with the base sodium hydroxide ($extNaOH$) to produce sodium sulfate ($ext{Na}_{2}ext{SO}_4$) and water ($ext{H}_{2}extO$).Understanding these reactions is fundamental in chemistry as it helps us comprehend how different substances interact and how they can be transformed.

Stoichiometry

Stoichiometry is the method used to calculate the quantities of reactants and products in a chemical reaction. It involves using a balanced chemical equation to determine the ratios needed for the calculation. In a neutralization reaction:

• You may need to calculate how much of one reactant you need to fully react with another.
• For instance, the balanced equation helps you understand how many moles of an acid are needed to react with a base.

Consider the equation$$ext{H}_{2}ext{SO}_4(aq)+2extNaOH(aq)ightarrowext{Na}_{2}ext{SO}_4(aq)+2ext{H}_{2}extO(l)$$Here, from the balanced equation, you know that one mole of$ext{H}_{2}ext{SO}_4$ will react with two moles of $extNaOH$.Using stoichiometry, you can predict the amount of each product that will form. It makes chemistry calculative and allows precise formulation in chemical manufacturing. Exploring stoichiometry can sharpen problem-solving skills as it involves conversions between different units like grams, moles, and molecule counts.