Question

1. the most abundant compound in most living things is a. carbon dioxide b. water c. sodium chloride d. sugar
2. when salt is dissolved in water, water is the a. reactant b. solution c. solute d. solvent
3. a map of eastern north america, showing the ph of rainfall of various states, indicates that the ph of rain in new york state varies from 4.22 to 4.40. according to these figures, the most acidic rainfall in new york state has a ph of a. 4.22 b. 4.30 c. 4.35 d. 4.40
4. a substance with a ph of 6 is called a. an acid b. a base c. both an acid and a base d. neither an acid nor a base
5. ice floats on a lake. this characteristic of water is responsible for a. altering migration patterns of birds b. mixing a lakes thermal layers c. suffocation of aquatic organisms d. preventing a lake from freezing solid
6. field data

pond ph of pond water number of duckweed plants
a 6 150
b 12 300
c 8 500
d 4 80
the above information was collected in the field while studying the effect of ph on the growth of the duckweed plant. the data shows that the optimum ph for the growth of the duckweed plant is a. 4 b. 6 c. 8 d. 12

Explanation:

1. Water is the most abundant compound in most living things.
2. When salt is dissolved in water, water is the solvent as it is the substance in which the solute (salt) is dissolved.
3. The lower the pH value, the more acidic the substance. Among 4.22 - 4.40, 4.22 is the most acidic.
4. Substances with pH less than 7 are acids. A substance with pH of 6 is an acid.
5. Ice floating on water helps prevent a lake from freezing solid as it acts as an insulator.
6. The pond with pH 8 has the highest number of duckweed plants, indicating it is the optimum pH for duckweed growth.

Answer:

1. b. water
2. d. solvent
3. a. 4.22
4. a. An acid
5. d. preventing a lake from freezing solid
6. c. 8