How do you predict the products of #"H"_2"SO"_4" + NaOH"#?

2 Answers
Jan 25, 2015

Learning how to predict the products of a chemical reaction requires instruction, experience, and research. Being able to recognize the type of chemical reaction will help you be able predict the products of the reaction. The reaction between sulfuric acid, #"H"_2"SO"_4"#, and the base sodium hydroxide, #"NaOH"#, is a neutralization reaction.

A neutralization reaction is a type of double replacement reaction in which the reactants are an acid and a base, and the products are a salt and water (acid + base #rarr# salt + water). A salt is an ionic compound that results from a neutralization reaction between an acid and a base. The chemical equation for this reaction is:

#"H"_2"SO"_4("aq")# + #"2NaOH(aq)"# #rarr# #"Na"_2"SO"_4("aq")"# + #"2H"_2"O(l)"#

#"Na"_2"SO"_4"# is the salt sodium sulfate.

Jan 25, 2015

In order to predict what the products of a chemical reaction will be you must first be familiar with the six types of chemical reactions: synthesis, decomposition, single replacement, double replacement, acid-base, and combustion.

I can't walk you through all of them since it would make for a very, very long answer; however, I'll show you in detail the example you have.

Each of these reaction types has typical characteristics that allow you to figure out what the products of the reaction will be. For example, the reaction you've chosen is an acid-base reaction (also known as a neutralization reaction).

In this particular case, a strong acid, #"H"_2"SO"_4#, reacts with a strong base, #"NaOH"#, to produce salt and water.

#H_2SO_(4(aq)) + 2NaOH_((aq)) -> Na_2SO_(4(aq)) + 2H_2O_((l))#

For this type of reaction you must also be familiar with complete and net ionic equations. Make sure that you understand what the #"(aq)"#, #"(s)"#, #"(g)"#, and #"(l)"# symbols means, since they play an important part in understanding what happens in a reaction.

In this case, the reaction takes place in aqueous solution, hence the #"(aq)"# symbols. When placed in solution, strong acids and bases will dissociate into cations and anions, like this:

#2H_((aq))^(+) + SO_(4(aq))^(2-) + 2Na_((aq))^(+) + 2OH_((aq))^(-) -> 2Na_((aq))^(+) + SO_(4(aq))^(2-) + 2H_2O_((l))#

This represent the complete ionic equation. If you eliminate the spectator ions, i.e. the ions present on both sides of the reaction, you'll get the net ionic equation

#H_((aq))^(+) + OH_((aq))^(-) -> H_2O_((l))#

As a conclusion, you must become familiar with the various types of chemical reactions if you wish to be able to say what the products of a reaction are.