Chemical Reactions (Junior Cert Science): Quizzes
📚Quizzes
Practise the questions
10 questions from this quiz
ShowHide
Practise the questions
10 questions from this quiz
What happens to substances during a physical change?
What happens to substances during a physical change?
Appearance changes but same material
Which is an example of a chemical change?
Which is an example of a chemical change?
Burning wood to produce ash and smoke
Which observation indicates a chemical reaction has occurred?
Which observation indicates a chemical reaction has occurred?
Gas is produced and bubbles are seen
What is the main difference in reversibility between physical and chemical changes?
What is the main difference in reversibility between physical and chemical changes?
Physical changes are easy to reverse
In the word equation Iron + Sulfur → Iron sulfide, what are the reactants?
In the word equation Iron + Sulfur → Iron sulfide, what are the reactants?
Iron and Sulfur
When balancing chemical equations, what can you change?
When balancing chemical equations, what can you change?
Numbers in front of formulas only
What does the law of conservation of mass state?
What does the law of conservation of mass state?
Total mass of reactants = mass of products
In Lavoisier's 1774 mercury experiment, what was the final mass?
In Lavoisier's 1774 mercury experiment, what was the final mass?
2,527.34 grams (same as start)
Why must conservation of mass experiments be done in a closed system?
Why must conservation of mass experiments be done in a closed system?
To prevent substances escaping or entering
Why is mass conserved according to particle theory?
Why is mass conserved according to particle theory?
Atoms are rearranged, not created/destroyed