Chemical Equations/Reactions! Created by Educational Technology Network. www.edtechnetwork.com 2009

Formulas Equations Signs of Reactions Everyday Reactions Vocabulary 10 10 10 10 10 20 20 20 20 20 30 30 30 30 30 40 40 40 40 40 50 50 50 50 50

Topic 1 – 10 Points QUESTION: The small number to the right of a chemical symbol that tells how many atoms of the element are present ANSWER: What is a subscript?

Topic 1 – 20 Points QUESTION: The larger number to the left of a chemical formula that tells how many molecules of the substance are present ANSWER: What is the coefficient?

Topic 1 – 30 Points QUESTION: They are the substances that take part in the reaction. They are represented by the chemical formulas to the left of the big arrow. ANSWER: What are the reactants?

Topic 1 – 40 Points QUESTION: They are the substances that are created by the reaction. They are represented by the chemical formulas to the right of the big arrow. ANSWER: What are the products?

Topic 1 – 50 Points QUESTION: Three chemical formulas for substances we use often. ANSWER: What are: H2O, CO2, H2O2 (other formulas are OK)

Topic 2 – 10 Points QUESTION: A shorthand way of representing an entire chemical reaction. It shows how the atoms were re-arranged. ANSWER: What is a chemical formula?

Topic 2 – 20 Points QUESTION: The substances represented by the formulas on the left of the arrow. They will be changed by the reaction. ANSWER: What are reactants?

Topic 2 – 30 Points QUESTION: The bonds between atoms are broken apart, and the atoms are re-arranged to create new substances. ANSWER: What happens in a chemical reaction?

Topic 2 – 40 Points QUESTION: An equation in which the number atoms of each element on the left are equal to the number of atoms of that same element on the right. ANSWER: What is a balanced chemical equation?

Topic 2 – 50 Points QUESTION: The mass of all reactants must equal the mass of all products. Matter (atoms) are neither created nor destroyed. ANSWER: What is the Law of Conservation of Mass (or Matter)?

Topic 3 – 10 Points QUESTION: In lab, a solid and a liquid are mixed. Students notice foamy bubbles appear. ANSWER: What is a sign of a gas being produced?

Topic 3 – 20 Points QUESTION: In a lab, two substances are combined in a baggie, and the students see the color change to bright pink? ANSWER: What is a sign of a chemical reaction (color change)?

Topic 3 – 30 Points QUESTION: In lab, students combine two substances in a baggie, and they notice heat coming from the bag. ANSWER: What is a sign of an exothermic chemical reaction?

Topic 3 – 40 Points QUESTION: In lab, students combine two substances in a baggie, and they notice that the bag feels cold. ANSWER: What is a sign of an endothermic chemical reaction?

Topic 3 – 50 Points QUESTION: In lab, students combine two chemicals in a baggie and notice that the liquid gets cloudy. ANSWER: What is a sign of chemical change (precipitate)?

Topic 4 – 10 Points QUESTION: I stir creamer into my coffee because I like the sweet taste. The coffee gets lighter in color. (physical or chemical) change? ANSWER: What is a physical change?

Topic 4 – 20 Points QUESTION: I write on the paper with my favorite purple pen. The paper now has purple lines. (physical or chemical) change? ANSWER: What is a physical change?

Topic 4 – 30 Points QUESTION: I fry an egg for breakfast. I notice that it changes from clear to white and bubbles around the edges. (physical or chemical) change? ANSWER: What is a chemical change?

Topic 4 – 40 Points QUESTION: A candle burns for two hours. I notice that some of the wax is gone. (physical or chemical) change? ANSWER: What is a chemical change?

Topic 4 – 50 Points QUESTION: I spill soda on the table and soak it up with a paper towel. The towel is now brown and soggy. (physical or chemical) change? ANSWER: What is a physical change?

Topic 5 – 10 Points QUESTION: Proof that you are able to notice with your senses. ANSWER: What is evidence?

Topic 5 – 20 Points QUESTION: 5 types of evidence for a chemical reaction. ANSWER: What are: (1) color change (2) gas produced (3) light produced (4) temperature change (5) precipitate formed

Topic 5 – 30 Points QUESTION: The process by which one or more substances change to produce one or more different substances. ANSWER: What is a chemical reaction?

Topic 5 – 40 Points QUESTION: A solid substance that forms in a liquid from a chemical reaction. ANSWER: What is a precipitate?

Topic 5 – 50 Points QUESTION: The part of the chemical equation that shows the process of re-arranging the atoms to become something new. ANSWER: What is the big arrow in the middle of the equation?