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What happens when an acid or a base is mixed with water? |
Decrease in the concentration of ions (H2O+/OH–) per unit volume Decrease in the concentration of ions (H3O+/OH–) per litre volume increase in the concentration of ions (H3O+/OH–) per unit volume Decrease in the concentration of ions (H3O+/OH–) per unit volume |
Decrease in the concentration of ions (H3O+/OH–) per unit volume |
The correct answer is option 4. Decrease in the concentration of ions \((H_3O^+/OH^–)\) per unit volume. Here's why: When an acid or base is mixed with water, it undergoes a process called dilution. This means that the concentration of the acid or base is decreased because it is spread out in a larger volume of water. Both acids and bases dissociate in water, meaning they break apart into their constituent ions. Acids typically release hydronium ions \((H_3O^+)\), while bases release hydroxide ions \((OH^-)\). By adding water, the total number of ions \((H_3O^+ \text{and }OH^-)\) remains the same, but the volume of the solution increases. Therefore, the concentration of ions per unit volume decreases. Therefore, option 4 correctly describes what happens when an acid or a base is mixed with water. |