The Conservation of Matter
Test your knowledge on the fundamental principle of the conservation of matter.
Questions
According to the law of conservation of mass, what remains constant in a chemical reaction?
- Mass of reactants
- Mass of products
- Total mass of reactants and products
- Volume of reactants
In a balanced chemical equation, the coefficients in front of the chemical formulas represent:
- The number of atoms of each element in the reaction
- The number of moles of each compound in the reaction
- The mass of each compound in the reaction
- The volume of each gas in the reaction
What is the mass of the products formed when 10 g of methane (CH4) reacts completely with 20 g of oxygen (O2)?
- 10 g
- 20 g
- 30 g
- 40 g
In a chemical reaction, 5 moles of hydrogen gas (H2) react with 3 moles of oxygen gas (O2) to form water (H2O). How many moles of water are produced?
- 3 moles
- 5 moles
- 8 moles
- 10 moles
Which of the following statements is true about the conservation of matter?
- Matter can be created or destroyed in a chemical reaction.
- Matter can change from one form to another, but its total mass remains constant.
- The mass of the reactants in a chemical reaction is always greater than the mass of the products.
- The volume of the reactants in a chemical reaction is always less than the volume of the products.
In a nuclear reaction, mass is converted into energy according to the equation E=mc2. Does this violate the law of conservation of mass?
- Yes, because mass is being destroyed.
- No, because energy and mass are equivalent.
- It depends on the specific nuclear reaction.
- The law of conservation of mass does not apply to nuclear reactions.
Which of the following is an example of a physical change that does not involve a change in the composition of matter?
- Melting ice
- Burning wood
- Rusting iron
- Digesting food
Which of the following is an example of a chemical change that involves a change in the composition of matter?
- Dissolving salt in water
- Boiling water
- Fermenting grapes
- Freezing water
In a chemical reaction, the reactants are converted into products. What happens to the mass of the reactants?
- It is destroyed.
- It is created.
- It remains constant.
- It changes.
What is the mass of the products formed when 20 g of sodium (Na) reacts completely with 35.5 g of chlorine (Cl2)?
- 20 g
- 35.5 g
- 55.5 g
- 71 g
In a chemical reaction, 4 moles of propane (C3H8) react completely with 13 moles of oxygen (O2) to form carbon dioxide (CO2) and water (H2O). How many moles of carbon dioxide are produced?
- 4 moles
- 6 moles
- 8 moles
- 10 moles
Which of the following statements is true about the conservation of matter?
- Matter can be created or destroyed in a chemical reaction.
- Matter can change from one form to another, but its total mass remains constant.
- The mass of the reactants in a chemical reaction is always greater than the mass of the products.
- The volume of the reactants in a chemical reaction is always less than the volume of the products.
In a nuclear reaction, mass is converted into energy according to the equation E=mc2. Does this violate the law of conservation of mass?
- Yes, because mass is being destroyed.
- No, because energy and mass are equivalent.
- It depends on the specific nuclear reaction.
- The law of conservation of mass does not apply to nuclear reactions.
Which of the following is an example of a physical change that does not involve a change in the composition of matter?
- Melting ice
- Burning wood
- Rusting iron
- Digesting food
Which of the following is an example of a chemical change that involves a change in the composition of matter?
- Dissolving salt in water
- Boiling water
- Fermenting grapes
- Freezing water