[2] Learning Catalytics

Question 1

The atomic number of carbon is 6. Carbon-14 is heavier than carbon-12 because the atomic nucleus of carbon-14 contains how many neutrons?

Answer 1

8.

Question 2

Carbon has an atomic number of 6 and a mass number of 12. How many electrons are needed to complete the valence shell of a carbon atom?

Answer 2

4.

Question 3

Based on the periodic table below and what you know about ions forming, which elements will most likely form an ionic bond?

Answer 3

Na and Cl

Question 4

Based on the periodic table below, which elements are most likely to form a covalent bond?

Answer 4

H & H

Question 5

Complete the analogy. Coavalent bonds are to ionic bonds as a wooden board is to ___.

Answer 5

paper

Question 6

Correct the following statement: “A double ionic bond can occur if the valence shells of the two participants allow for sharing two electrons.”

Answer 6

A double covalent bond can occur if the valence shells of two participants allow for sharing four electrons.

Question 7

The gecko can climb smooth walls due to one type of bond or interaction, whereas a spider can walk on water due to a different kind. Identify each type of bond.

Answer 7

van der Waals, hydrogen bonds

Question 8

If the cytoplasm of a cell is at pH 8, and the interior of an organelle is pH 7, this means that…

Answer 8

the concentration of hydrogen ions is tenfold higher in the organelle than in the cytoplasm

Question 9

One liter of a solution of pH 5 has how many more hydrogen ions (H+) than 1 L of a solution of pH 9?

Answer 9

10000 times more

Question 10

What are the four emergent properties of water that are important for life?

Answer 10

cohesion, moderation of temperature, expansion upon freezing, solvent properties

Question 11

Water has an unusually high specific heat. This is directly related to which of the following?

Answer 11

More heat is required to raise the temperature of water.

Question 12

Temperatures depend on local geographic conditions. Why is the temperature much cooler in Wilmington than in Greensboro?

Question 13

You are asked whether a sample came from a living thing. Chemical analysis shows that it consists mostly of calcium and sulfur, so you say that:

Answer 13

it did not, since living things contain more carbon and oxygen than most other elements

Question 14

If you see radioactive isotopes in a laboratory that deals with biological samples, what is the least likely reason they are present?

Answer 14

disinfecting wounds