a.Oxygen (O) makes up 46.7% by mass of Earth’s crust.How many grams of oxygen are present...

a.Oxygen (O) makes up 46.7% by mass of Earth’s crust.

How many grams of oxygen are present if a sample of the crust has a mass of 325 g?

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b. Magnesium (Mg) makes up 2.1% by mass of Earth’s crust. How many grams of magnesium are present if a sample of the crust has a mass of 1.25 g?

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c. A plant fertilizer contains 15% by mass nitrogen (N). In a container of soluble plant food, there are 10.0 oz of fertilizer. How many grams of nitrogen are in the container?

Agricultural fertilizers applied to a field provide nitrogen for plant growth.

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d. In a candy factory, the nutty chocolate bars contain 22.0% by mass pecans. If 5.0 kg of pecans were used for candy last Tuesday, how many pounds of nutty chocolate bars were made?