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Practice Questions
Test your understanding with targeted questions related to the topic.
Question 1
Easy
Calculate how many moles are in 40.08 g of calcium (Ca).
💡 Hint: Use the molar mass formula: Moles = Mass / Molar Mass.
Question 2
Easy
How many molecules are in 2.50 moles of NaCl?
💡 Hint: Multiply moles by Avogadro's constant, which is 6.022 × 10²³.
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 molar mass of water (H₂O)?
- 16.02 g/mol
- 18.02 g/mol
- 20.02 g/mol
💡 Hint: Calculate using the atomic mass from the periodic table.
Question 2
True or False: 1 mole of any substance contains exactly 6.022 × 10²³ particles.
- True
- False
💡 Hint: Think about how the mole relates to Avogadro's constant.
Solve and get performance evaluation
Challenge Problems
Push your limits with challenges.
Question 1
A reaction produces 5.0 moles of ammonia (NH₃) from nitrogen (N₂) and hydrogen (H₂). If the balanced equation is N₂ + 3H₂ → 2NH₃, how many grams of N₂ are needed?
💡 Hint: Don’t forget to convert moles of N₂ to grams using its molar mass.
Question 2
How many grams of O₂ are needed to produce 150 g of CO₂ from the reaction C + O₂ → CO₂?
💡 Hint: Ensure you're balancing the equation correctly.
Challenge and get performance evaluation