15. Which type of reaction takes place in the presence of oxygen gas and produces carbon dioxide and water? a. decomposition b synthesis C. combustion d. double replacement 16. In an experiment,a white solid is mixed into a clear liquid and the following changes were observed. Which of these changes is NOT evidence that a chemical reaction took place? a. The solid dissolved into solution b. The liquid turned blue C. The liquid started bubbling d. Agas was released by the solutions 17. What is the balanced coefficient for AgNO_(3)?underline ( )Cu+underline ( )AgNO_(3)arrow underline ( )Ag+underline ( )Cu(NO_(3))_(2) a. 1 b. 2 C. 4 d. 3 18. What type of reaction is this? 2KClO_(3)arrow 2KCl+3O_(2) a. decomposition b. double replacement C. synthesis d. single replacement 19. Which chemical equation is correctly balanced? (Choose TWO correct answers) a. KClarrow K+Cl_(2) b. 2KClarrow 2K+Cl_(2) C. 4KClarrow 4K+2Cl_(2) d. 2KClarrow K+Cl_(2) 20. Which compound in the following equation is the precipitate? BaCl_(2(aq))+H_(2)SO_(4(aq))arrow BaSO_(4(s))+2HCl_((aq)) a. BaCl_(2(aq)) b. BaSO_(4(s)) C. H_(2)SO_(4(aq)) d. HCl_((aq)) 21. The chemical reaction below would represent a-BaBr_(2)+Na_(3)PO_(4)arrow Ba_(3)(PO_(4))_(2)+NaBr a. double replacement reaction b. synthesis reaction C. single replacement reaction d. decomposition reaction