Barbara completed an assignment for extra credit in science class. She used a pH meter to find the pH of different substances.

Question

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.

If Barbara added lemon juice—pH 2.2—to her investigation, where should it appear in her diagram?
A.
to the left of cola
B.
between milk and water
C.
between water and blood
D.
between soap and bleach

Answer 1

To determine the position of lemon juice (pH 2.2) in Barbara's diagram arranged from most acidic to most basic, we need to look at the common pH values of the substances mentioned:

• Lemon juice: pH 2.2 (acidic)
• Cola: pH around 2.5 (acidic)
• Milk: pH around 6.5 (slightly acidic)
• Water: pH 7 (neutral)
• Blood: pH around 7.4 (slightly basic)
• Soap: pH around 9 (basic)
• Bleach: pH around 12-13 (very basic)

Given this information, lemon juice (pH 2.2) would be more acidic than cola (pH 2.5), and significantly more acidic than milk (pH 6.5). Therefore, it should be placed to the left of cola.

The correct answer is: A. to the left of cola.