Question
question 20
In a recent year, the federal government removed Rocky gray wolf from the list of endangered resulting in the first Rocky gray wolf hunting in decades. During this season, about one-fourth of the population, or an estimated 500 wolves, were killed. Approximately how may Rocky gray wolves had lived in the wild before the hunt began? (Source:) In chemistry, an endothermic reaction is one that heat. As a result of an endothermic reaction, the temperate of a solution dropped by 19.8 degrees Celsius to 7.6 degree C. What was the temperature of the solution before the reaction took place? (Source: Timberlake, Chemistry: An Introduction to General, Organic, and Biological Chemistry)
Explanation / Answer
Let the temperature of the solution before reaction was T oC.
From, the question, the drop in the temperature (dT) after reaction is 19.8 oC and reached (Tf) to 7.6 oC.
dT=19.8 oC and Tf =7.6 oC
so, Tf = T - dT
or, T = Tf + dT
put the value of Tf and dT in above equation.
T = 7.6 + 19.8 = 27.4
T = 27.4 oC