1.) A student performs a reaction and determines the enthalpy change (H) to be 31.4 kJ....
1.) A student performs a reaction and determines the enthalpy change (H) to be 31.4 kJ. Will the temperature of the surrounding solution increase or decrease as a result of this chemical process?
2.) If you hold 3 grams of ice in your hand at room temperature, your hand will become cold.
a.) Is the reaction H2O (s) ----> H2O (l) endothermic or exothermic?
b.) In which direction does heat flow?
Homework Answers
1)
Delta H is positive.
So, system absorbs heat from surrounding.
Since surrounding is losing heat, temperature of surrounding will
decrease
Answer: decrease
2)
a)
Hand is becoming cold when solid is changing to gas.
That means hand is losing heat and the process is gaining
heat.
So, the process is endothermic
Answer: endothermic
b)
Heat flows from Gand to system
Add Answer to:
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