1)(PUC-MG) Sejam dadas as equações termoquímicas, todas a 25 °C e 1 atm. I- H2(g) + 1/2O2(g) →H₂O AH = -68,3 Kcal/mol
II- 2Fe()+ 3/2 O2(g) Fe₂O3(s) AH = -196,5 Kcal/mol
III- 2Al(s) + 3/2 O2(g) Al2O3(s) AH = -399,1 Kcal/mol
IV-C(grafite) + O2(g) → CO2(g) AH = -94,0 Kcal/mol
V- CH4(g) + O2(g) →→ CO2(g) + H₂O AH = -17,9 Kcal/mol Exclusivamente sob o ponto de vista energético, das reações acima, a que você escolheria como fonte de energia é:
A)I
B)II
C)III
D)IV
E)V

Janel’s class studied properties of matter and how matter can change. janel decided she would do an experiment mixing baking soda and vinegar.question: describe the properties of baking soda and vinegar, and explain the changes that janel should see when she mixes the two types of matter. •first, identify the physical state of matter of baking soda. describe another property of baking soda. •next, identify the physical state of matter of vinegar. describe another property of vinegar. •then, explain what janel should see when she mixes the baking soda and vinegar. •describe the states of matter of the new materials that are formed. •explain how janel can be certain a change has occurred. me

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