The initial temperature is 137.34 °C.
<u>Explanation:</u>
As the specific heat formula says that the heat energy required is directly proportional to the mass and change in temperature of the system.
Q = mcΔT
So, here the mass m is given as 23 kg, the specific heat of steel is given as c = 490 J/kg°C and the initial temperature is required to find with the final temperature being 140 °C. Also the heat energy required is 30,000 J.
ΔT =
ΔT =
Since the difference in temperature is 2.66, then the initial temperature will be
Final temperature - Initial temperature = Change in temperature
140-Initial temperature = 2.66
Initial temperature = 140-2.66 = 137.34 °C
Thus, the initial temperature is 137.34 °C.
If this is a true or false question then the answer is true.
1. Observation-- making observations and taking notes about what you see, smell, hear, think, etc.
2. Question-- developing a question to test your observations.
3. Hypothesis-- creating an educated guess as to the answer of your question.
Answer:
The options <u>(A) -</u>The rate law for a given reaction can be determined from a knowledge of the rate-determining step in that reaction's mechanism. and <u>(C) </u>-The rate laws of bimolecular elementary reactions are second order overall ,<u>is true.</u>
Explanation:
(A) -The rate law can only be calculated from the reaction's slowest or rate-determining phase, according to the first sentence.
(B) -The second statement is not entirely right, since we cannot evaluate an accurate rate law by simply looking at the net equation. It must be decided by experimentation.
(C) -Since there are two reactants, the third statement is correct: most bimolecular reactions are second order overall.
(D)-The fourth argument is incorrect. We must track the rates of and elementary phase that is following the reaction in order to determine the rate.
<u>Therefore , the first and third statement is true.</u>