Question

barbara completed an assignment for extra credit in science class. she used a ph meter to find the ph of different substances. after she finished measuring the phs, she created a diagram that showed the substances arranged in order from the most acidic to the most basic. diagram with cola, acid rain (5.0), milk (6.8), water (7.0), blood (7.4), soap (9.0), bleach (12.8) a barbara added stomach acid—ph 1.3—to her investigation, where should it appear in her diagram?
a. to the left of cola
b. between water and blood
c. between soap and bleach

Explanation:

The pH scale measures acidity (lower pH, more acidic) and basicity (higher pH, more basic). Cola has a pH (let's assume from the diagram's order, cola is more acidic than acid rain? Wait, no—wait, the diagram's order: cola, acid rain (pH 5.0), milk (6.8), water (7.0), blood (7.4), soap (9.0), bleach (12.6). Wait, no, the pH values: cola's pH (from typical cola, around 2 - 3, but in the diagram, cola is red, then acid rain (5.0). Wait, the question: stomach acid has pH 1.3. Lower pH means more acidic. So cola's position: if cola is to the left of acid rain (pH 5.0), then stomach acid (pH 1.3) is more acidic than cola (since 1.3 < cola's pH, assuming cola's pH is higher than 1.3, like 2 - 3). So more acidic substances are to the left. So stomach acid (pH 1.3) is more acidic than cola, so it should be to the left of cola. Option A says to the left of cola, which makes sense. Option B: between water (7.0) and blood (7.4) – those are neutral to slightly basic, so stomach acid (acidic) can't be there. Option C: between soap (9.0) and bleach (12.6) – both basic, so no. So the correct answer is A.

Answer:

A. to the left of cola