Which of the following substances would most likely demonstrate a higher pH?

Baking soda is a basic compound, which means it has a higher pH compared to the other options listed. The pH scale measures how acidic or basic a substance is, with lower values (below 7) indicating acidity and higher values (above 7) indicating basicity.

In this context, lemon juice and vinegar are both acidic, typically having pH values below 7. Soda, while it can vary, is generally also acidic due to its carbonation and the presence of phosphoric acid, which further reinforces its lower pH level.

Baking soda, being sodium bicarbonate, has a pH around 9 to 10 when dissolved in water, making it distinctly more basic than the acidic options. This characteristic of baking soda is why it is commonly used in baking as a leavening agent, as it reacts with acids to produce carbon dioxide gas. Thus, among the options provided, baking soda is the substance most likely to demonstrate a higher pH.