- Basic Math and Science Chemical Reactions and Stoichiometry Questions and Answers Flashcards
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Read the first 6 - Basic Math and Science Chemical Reactions and Stoichiometry Questions and Answers flashcards as text
What is Avogadro's number?
Answer: 6.022 × 10²³
Avogadro's number (6.022 × 10²³) is the number of particles in one mole of any substance.
Balance the equation: __Al + __O₂ → __Al₂O₃
Answer: 4Al + 3O₂ → 2Al₂O₃
4 Al atoms on each side (4 left, 2×2 right) and 6 O atoms on each side (3×2 left, 2×3 right).
What is the limiting reagent?
Answer: The reactant that is completely consumed first, determining the maximum product
The limiting reagent runs out first and limits how much product can be formed.
What is an exothermic reaction?
Answer: A reaction that releases heat to the surroundings
Exothermic reactions release energy as heat, making the surroundings warmer.
If 2 moles of H₂ react with excess O₂, how many moles of H₂O are produced? (2H₂ + O₂ → 2H₂O)
Answer: 2 moles
The mole ratio of H₂ to H₂O is 2:2, or 1:1. So 2 moles of H₂ produce 2 moles of H₂O.
What happens to the rate of a reaction when temperature increases?
Answer: The rate increases
Higher temperature gives particles more kinetic energy, leading to more frequent and energetic collisions.