Homework Practice

Printable assignment

pH in Real Life: Stomach, Teeth, Soil and Water

Section A: pH Scale and Hydrogen Ions

Question 1mcq

A solution with pH 7 is:

A.Strongly basic

B.Always poisonous

C.Strongly acidic

D.Neutral

Question 2mcq

A solution with pH 3 is:

A.Basic

B.Alkaline only

C.Neutral

D.Acidic

Question 3mcq

A solution with pH 11 is:

A.Neutral

B.Acidic

C.A gas

D.Basic

Question 4mcq

Lower pH means:

A.No ions

B.Higher

H^+

ion concentration

C.More

OH^-

always

D.Lower acidity

Question 5mcq

Which is more acidic: pH 2 or pH 5?

A.pH cannot compare acidity

B.Both neutral

C.pH 5

D.pH 2

Question 6mcq

Universal indicator helps estimate:

A.pH range

B.Temperature only

C.Mass only

D.Volume only

Section B: pH in Everyday Life

Question 7mcq

The acid in our stomach is mainly:

A.Hydrochloric acid

B.Acetic acid

C.Carbonic acid

D.Nitric acid in large quantity

Question 8mcq

Antacids help because they are:

A.Strong acids

B.Neutral gases

C.Mild bases that neutralise excess stomach acid

D.Indicators only

Question 9mcq

Tooth decay can start when mouth pH falls below about:

A.7.5

B.14

C.10

D.5.5

Question 10mcq

Toothpaste is often basic because it helps:

A.Make mouth more acidic

B.Neutralise acids in the mouth

C.Produce sugar

D.Remove all saliva

Question 11mcq

If soil is too acidic, farmers may add:

A.More acid

B.Vinegar

C.Sugar solution

D.Slaked lime

Question 12mcq

Sudden pH change in a lake can harm fish because:

A.pH has no effect

B.Fish need pH 0 only

C.Aquatic organisms survive within a suitable pH range

D.Only colour changes matter