Question

If \(1000 \mathrm{NaOH}\) units were dissolved in a sample of water, the \(\mathrm{NaOH}\) would produce ______ \(\mathrm{Na}^{+}\) ions and ________ \(\mathrm{OH}^{-}\) ions.

Short answer

The dissolution of 1000 units of NaOH in water produces 1000 Na+ ions and 1000 OH- ions.

Step-by-step solution

Write the dissociation reaction of NaOH in water

When NaOH dissolves in water, it dissociates into its ions, Na+ and OH-. The balanced chemical equation for this process is: \[ \mathrm{NaOH} \rightarrow \mathrm{Na}^{+} + \mathrm{OH}^{-} \]

Apply stoichiometry to find the amount of Na+ and OH- ions

According to the balanced equation, one molecule of NaOH dissociates into one Na+ ion and one OH- ion. Since we have 1000 units of NaOH, we can apply stoichiometry to find the amounts of Na+ and OH- ions produced: \[ 1000 \, \mathrm{NaOH} \, \frac{1 \, \mathrm{Na}^{+}}{1 \, \mathrm{NaOH}} = 1000 \, \mathrm{Na}^{+} \] \[ 1000 \, \mathrm{NaOH} \, \frac{1 \, \mathrm{OH}^{-}}{1 \, \mathrm{NaOH}} = 1000 \, \mathrm{OH}^{-} \]

State the amounts of Na+ and OH- ions produced

Based on the stoichiometry, the dissolution of 1000 units of NaOH in water produces: - 1000 Na+ ions - 1000 OH- ions

Key concepts

Stoichiometry

Stoichiometry is a branch of chemistry that deals with the quantitative relationships between the reactants and products in a chemical reaction. When you're using stoichiometry, you rely on balanced chemical equations to determine these relationships. This helps predict how much of a substance is needed or produced in a given reaction.

In the context of the dissociation of sodium hydroxide ( NaOH ) in water, stoichiometry tells us that each unit of NaOH produces one sodium ion ( Na^{+} ) and one hydroxide ion ( OH^{-} ).

• If you start with 1000 units of NaOH, stoichiometry makes it straightforward to calculate the amounts of ions produced. Each NaOH produces exactly one of each ion, so with 1000 units, you'll get 1000 sodium ions and 1000 hydroxide ions.
• By understanding stoichiometry, you can work out the amounts of all substances in a chemical reaction, which is crucial for any quantitative chemical analysis.

This approach is key for both simple and complex reactions, ensuring you grasp the relationship between different chemical species.

Chemical Equations

Chemical equations are symbolic representations of chemical reactions. They describe the reactants transforming into products, indicating their molecular composition and the stoichiometric proportions.

In the example of NaOH dissolving in water, the chemical equation can be written as follows:
\[\mathrm{NaOH} \rightarrow \mathrm{Na^{+}} + \mathrm{OH^{-}} \]

• This equation tells us that solid NaOH dissociates into Na^{+}and OH^{-} ions in solution.
• The arrow in the equation shows the direction of the reaction, typically from left (reactants) to right (products).
• In this case, there's a one-to-one ratio of NaOH to Na^{+}and OH^{-} ions.

By looking at chemical equations, you can learn about the changes occurring in a reaction and use that information for calculations, such as determining amounts of products formed from given reactants.

Ions in Solution

When ionic compounds like sodium hydroxide (NaOH) dissolve in water, they separate into ions. This process, known as dissociation, is crucial for understanding many chemical behaviors and reactions in aqueous solutions.

For NaOH, the dissociation in water looks like this:
\[\mathrm{NaOH}(s) \rightarrow \mathrm{Na^{+}}(aq) + \mathrm{OH^{-}}(aq)\]

• Here, the (aq) symbol indicates that the ions are aqueous, meaning they are surrounded by water molecules and free to move within the solution.
• The sodium ions (Na^{+}) and hydroxide ions (OH^{-}) resulting from this reaction are responsible for the basicity of the solution.
• In practical terms, this is why NaOH is commonly used in laboratories and industrial processes as a strong base.

Understanding ions in solution helps you predict and explain behaviors like conductivity, reactivity, and the properties of the solutions created.