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Practice Questions
Test your understanding with targeted questions related to the topic.
Question 1
Easy
Calculate the molecular mass of water (H2O).
💡 Hint: Add the atomic masses of hydrogen and oxygen.
Question 2
Easy
What is the mass percent of hydrogen in H2O?
💡 Hint: Use the formula and remember to multiply by 100.
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 is the formula for percentage composition?
- (mass of element / molar mass of compound) x 100%
- (molar mass of compound / mass of element) x 100%
- (mass of compound / mass of element) x 100%
💡 Hint: Remember the relationship between mass of a part and whole.
Question 2
True or False: Molar mass is the total mass of a single atom of an element.
- True
- False
💡 Hint: Think about how many atoms are in a mole.
Solve and get performance evaluation
Challenge Problems
Push your limits with challenges.
Question 1
Analyze a sample containing 33g of sodium in 100g of sodium chloride. What is the percentage composition of sodium in NaCl?
💡 Hint: Find total mass of the compound first.
Question 2
Given a compound contains 12g of hydrogen, 48g of carbon, and 48g of oxygen, find the empirical formula.
💡 Hint: Convert to moles and simplify the ratios.
Challenge and get performance evaluation