Regents Chemistry Test Preparation Practice

    Entropy

    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11

    Base your answers to questions 12 on the information below and on your knowledge of chemistry.

    Fruit growers in Florida protect oranges when the temperature is near freezing by spraying water on them. It is the freezing of the water that protects the oranges from frost damage. When H2O(ℓ) at 0°C changes to H2O(s) at 0°C, heat energy is released. This energy helps to prevent the temperature inside the orange from dropping below freezing, which could damage the fruit. After harvesting, oranges can be exposed to ethene gas, C2H4, to improve their color.

    12

    Base your answers to questions 13 on the information below and on your knowledge of chemistry.

    Hydrazine, N2H4, is a compound that is very soluble in water and has a boiling point of 113°C at standard pressure. Unlike water, hydrazine is very reactive and is sometimes used as a fuel for small rockets. One hydrazine reaction producing gaseous products is represented by the balanced equation below.

    N2H4(ℓ) → N2(g) + 2H2(g) + heat

    13
    14

    Base your answers to questions 15 on the information below and on your knowledge of chemistry.

    The balanced equation below represents the reaction of glucose, C6H12O6, with oxygen at 298 K and 101.3 kPa.

    C6H12O6(s) + 6O2(g) → 6CO2(g) + 6H2O(ℓ)

    15