Answer:
So, Luke and Sian has to increase the pH of the soil by adding base to it.
Explanation:
The pH is defined as the negative logarithm of the hydrogen ion concentration in their aqueous solution.
- With increase in hydrogen ion concentration the pH value decreases.
- With decrease in hydrogen ion concentration the pH value increases.
The pH of the soil after testing it on a kit comes out be 5.0, but they both need pH of the soil to 6.5.
Comparison of pH of soil:
= 5.0 < 6.5
= High hydrogen ion concentration > High hydrogen ion concentration
So, Luke and Sian has to increase the pH of the soil by adding base .Doing so will decrease the hydrogen ion concentration in the soil (where as addition of acid lower the pH of soil).