Everyday Compound or Poison?

What happens when the atoms of a substance are regrouped?

• gold becomes malleable

• the atoms break apart and disappear

• a new substance is formed

• the substance stays the same

The creation of carbon monoxide is an effect. What is one cause?

• the regrouping of the atoms in table salt

• the burning of fossil fuels

• cleaning swimming pools

• operating a stove

Table salt can be separated into sodium and chlorine. Sodium is explosive. Chlorine is a gas that can kill people.

What can be concluded from the statements above?

• A harmful compound can become harmless when its elements are separated.

• A harmless compound can become harmful when its elements are separated

• Breaking a compound into its separate elements has no noticeable effects.

• Breaking a compound into its separate elements can create carbon dioxide.

Based on the information in the passage, what is true of gases?

• Some, but not all, gases are harmful to humans

• Any gas with carbon in it is not harmful to humans.

• All gases are harmful to humans.

• No gases are harmful to humans.

What is this passage mainly about?

• Germany's use of chlorine in World War I as a chemical weapon

• hydrochloric acid, aspartame, fructose, citric acid, and gelatin production

• the similarities and differences between carbon dioxide and carbon monoxide

• changes in chemical compounds and the effects of those changes

Read the following sentences:

"When the atoms of a specific substance are regrouped, a new substance is formed with often vastly different properties from the original substance. Occasionally something completely harmless, or even necessary, can become dangerous or lethal when its molecules (a grouping of two or more atoms) are regrouped."

What does the word properties mean above?

• extremely large amounts

• places where experiments are done

• qualities or characteristics

• elements or compounds

Oxygen by itself is not harmful; _______, it can become harmful when combined with carbon.

• however

• for instance

• in summary

• namely