answer all please

12) Which of the following does NOT 0/3 indicate that a chemical change may have taken place? energy transfer state of matter changes gas production precipitate formation 5) What are the missing coefficients foro/3 the skeleton equation below? Al2(SO4)3(aq)+KOH(aq)Al(OH)3(aq)+K2SO4(aq)1,6,2,32,12,4,61,3,2,34,6,2,3 19a) Write and balance the following 3/9 equation. Include state symbols. Solid gold (III) oxide breaks down into its elements. Individual feedback missing state symbols equation is not balanced 19b) Identify the reaction type 0/3 synthesis decomposition single-replacement double-replacement combustion