A desalination plant produces 200 gigalitres (GL) of fresh water each year. The maximum level of boron permitted in desalinated water is 0.5 ppm (0.5 mg L -1 ). The maximum mass, in kilograms, of boron that is permitted in one year production of desalinated water is: A. 9.26 x 10 3 B. 1.0 x 10 5 C. 1.08 x 10 6 D. 1.0 x 10 8

SSCE VCE Chemistry Chemical Elements: A desalination plant produces 20

A desalination plant produces 200 gigalitres (GL) of fresh water each year - VCE - SSCE Chemistry - Question 14 - 2012 - Paper 1

Question 14

A desalination plant produces 200 gigalitres (GL) of fresh water each year. The maximum level of boron permitted in desalinated water is 0.5 ppm (0.5 mg L-1</su... show full transcript

Worked Solution & Example Answer:A desalination plant produces 200 gigalitres (GL) of fresh water each year - VCE - SSCE Chemistry - Question 14 - 2012 - Paper 1

Step 1

Calculate the total volume of water in liters

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Answer

Since 1 gigalitre is equal to 1 billion liters (1 GL = 109 L), the total volume of water produced in one year by the desalination plant is:

200 ext{ GL} = 200 imes 10^9 ext{ L} = 2.0 imes 10^{11} ext{ L}

Step 2

Determine the maximum boron concentration

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Answer

The maximum permitted level of boron in the desalinated water is 0.5 mg L-1. This means that for every liter of water, there can be a maximum of 0.5 mg of boron.

Step 3

Calculate the total mass of boron

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Answer

To find the total mass of boron allowed in the entire volume of desalinated water, we can use the formula:

ext{Total mass of boron} = ext{Volume} imes ext{Concentration}

Substituting the values:

ext{Total mass of boron} = 2.0 imes 10^{11} ext{ L} imes 0.5 ext{ mg L}^{-1} = 1.0 imes 10^{11} ext{ mg}

Next, we need to convert milligrams to kilograms:

1.0 imes 10^{11} ext{ mg} = rac{1.0 imes 10^{11}}{10^6} ext{ kg} = 1.0 imes 10^5 ext{ kg}

Step 4

Select the correct answer

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Answer

From the calculations above, the maximum mass of boron permitted in one year production of desalinated water is 1.0 x 105 kg, which corresponds to option B.

A desalination plant produces 200 gigalitres (GL) of fresh water each year - VCE - SSCE Chemistry - Question 14 - 2012 - Paper 1

Worked Solution & Example Answer:A desalination plant produces 200 gigalitres (GL) of fresh water each year - VCE - SSCE Chemistry - Question 14 - 2012 - Paper 1

Calculate the total volume of water in liters

Determine the maximum boron concentration

Calculate the total mass of boron

Select the correct answer

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