A Sample of Water Has a Mass of 10

question 33

Multiple Choice

A sample of water has a mass of 10.0 grams. What is the number of molecules of water in the sample? (H = 1 u, O = 16 u, and 1 u = 1.66 × 10⁻²⁷ kg.)

• A) 1.99 × 10²³
• B) 2.00 × 10²³
• C) 2.56 × 10²³
• D) 3.35 × 10²³
• E) 4.25 × 10²³

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Definitions:

Clean Water Act

In environmental law, a federal statute that sets requirements for limiting the pollution of the nation’s water sources according to a schedule, based on the most effective technology currently available.

Pollutants

Substances that contaminate the environment, causing harm or discomfort to living organisms.

Waterways

Natural or man-made bodies of water, used for transportation, power, or irrigation.

Supremacy Clause

A principle in the U.S. Constitution that states federal laws and treaties have authority over conflicting state laws.