Chemical Reactions 8.5E Chemical Reactions Re-templated JPh 7/31 Matter and Energy Chemical Reactions Part I: Chemical Reactions and Equations CaCl2 + Na2CO3 → CaCO3 + 2NaCl Is this equation balanced? ______________________________________________________________________ Circle the reactants and place a box around the products. Write the equation as a sentence. ____________________________________________________________________________________________________________________________________________ Na2CO3 + 2H2O → 2NaOH + H2CO3 Is this equation balanced? ______________________________________________________________________ Write the equation as a sentence. ____________________________________________________________________________________________________________________________________________ Na2CO3 + 2CH3COOH → 2NaCH3COO + H2CO3 Is this equation balanced? ______________________________________________________________________ What are the four signs of a chemical reaction? ______________________________________________________________________ 8.5E Chemical Reactions Re-templated JPh 7/31 1 1

Part II: Signs of a Chemical Reaction Using Known Reactants Chemical Reactions Matter and Energy Part II: Signs of a Chemical Reaction Using Known Reactants Fill in your own information first, and then collect the rest of the data from your lab group (and share your own). Physical Properties (observed with hand lens) Observations During a Chemical Reaction when Mixed with Water Observations During a Chemical Reaction when Mixed with Vinegar Calcium Chloride Magnesium Sulfate Sodium Carbonate Citric Acid 2

Part III: Identifying Unknown Reactants Chemical Reactions Matter and Energy Part III: Identifying Unknown Reactants Fill in your own information first, and then collect the rest of the data from your lab group (and share your own). Physical Properties (observed with hand lens) Observations During a Chemical Reaction when Mixed with Water Observations During a Chemical Reaction when Mixed with Vinegar Which Unknown Reactants? Mixture A Mixture B Mixture C Mixture D 3

Reflections and Conclusions Chemical Reactions Matter and Energy Reflections and Conclusions How were the chemical reactions of the white solids similar? How were they different? ___________________________________________________________________________________________________________________________________________________________________________________________________________________________ Was a new substance with new properties produced when Unknown mixture A was combined with water or vinegar? Explain. __________________________________________________________________________________________________________________________________________________ Was a new substance with new properties produced when Unknown mixture B was combined with water or vinegar? Explain. __________________________________________________________________________________________________________________________________________________ Was a new substance with new properties produced when Unknown mixture C was combined with water or vinegar? Explain. __________________________________________________________________________________________________________________________________________________ Was a new substance with new properties produced when Unknown mixture D was combined with water or vinegar? Explain. __________________________________________________________________________________________________________________________________________________ What was the identity of your unknown mixture? What evidence leads you to believe this? ___________________________________________________________________________________________________________________________________________________________________________________________________________________________ Which of the unknown solids together could be used to make a cold pack? _________________________________________________________________________ Which of the unknown solids could be used to make a heat pack? _________________________________________________________________________ 4