|Question 27Verbal

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While researching a topic, a student has taken the following notes:

• Element abundance is a relative measure of the occurrence of a chemical element in a given environment.
• An element's relative abundance can be expressed as a mass fraction, mole fraction, or volume fraction.
• Mass fraction is the ratio of an element's mass to the combined mass of all elements in a given environment.
• The mass fraction of calcium (Ca) is 17,100 parts per million (ppm), or 1.71%, on Earth.
• The mass fraction of potassium (K) is 160 ppm, or 0.016%, on Earth.
The student wants to specily an element's relative abundance on Earth. Which choice most effectively uses relevant information from the notes to accomplish this goal?
Mass fraction, mole fraction, and volume fraction can all be used to express an element's relative abundance in a given environment.
A
Expressed as a mass fraction, the relative abundance of potassium on Earth is 160 ppm, or 0.016%.
B
The relative abundance of the element potassium on Earth can be expressed in three different ways.
C
On Earth, the mass fraction of potassium is greater than that of calcium.
D