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Practice Questions
Test your understanding with targeted questions related to the topic.
Question 1
Easy
Calculate the percent composition of oxygen in H₂O, given that the molar mass of water is 18.02 g/mol.
💡 Hint: Use the formula for percent composition.
Question 2
Easy
What does 2.0 ppm mean in terms of mass?
💡 Hint: Remember the definition of ppm.
Practice 4 more questions and get performance evaluation
Interactive Quizzes
Engage in quick quizzes to reinforce what you've learned and check your comprehension.
Question 1
What formula is used to calculate percent by mass?
💡 Hint: Think about how to express a fraction as a percentage.
Question 2
1 ppm is equivalent to ____ mg of solute in 1 kg of solution.
- 1 mg
- 0.01 mg
- 1000 mg
💡 Hint: Recall the definition of ppm.
Solve 1 more question and get performance evaluation
Challenge Problems
Push your limits with challenges.
Question 1
A solution contains 4.5 g of sodium chloride in 600 g of solution. Calculate the percent by mass of sodium chloride, and then determine its ppm in the same solution.
💡 Hint: Use the definitions for both percent mass and ppm to guide your calculations.
Question 2
A water sample has 0.012 g of a contaminant in 2 kg of water. Calculate the concentration in both ppm and ppb.
💡 Hint: Convert all masses to the appropriate units before applying the formulas.
Challenge and get performance evaluation