The correct answer among the choices given is the first option.The teacher most likely is talking about distillation of a mixture. Distillation is a unit operation that separates component substances from a liquid mixture which is shown by the teacher. Also, the most common purifying technique in the production of gasoline is by this process.
According to the question, the determined melting point of the compound is 112.5-113.0oC. When the solidified compound was retried, the melting point was found to be 133.6-154.5oC. This greater range higher than 112°C is caused by reusing samples leads to errors.
A pure sample is known by its sharp melting point. A pure sample does not melt over a large range. We can see this in the predetermined melting points of the pure sample(112.5-113.0oC).
However, reusing a sample introduces errors because the pure sample may become contaminated leading to a larger and higher range of melting point (133.6-154.5oC) which is far above 112°C.
Learn more: brainly.com/question/5325004
Answer:
The final state of the substance is a gas.
The sample is initially a liquid. One or more phase changes will occur.
Explanation:
Let's consider the phase diagram for Argon (not to scale).
<em>A sample of argon is initially at a pressure of 49.6 atm and a temperature of 101.4 K. The pressure on the sample is reduced to 0.680 atm at a constant temperature of 101.4 K. Which of the following are true? Choose all that apply </em>
<em>The final state of the substance is a gas.</em> TRUE. At 0.680 atm and 101.4 K, the substance is a gas.
<em>The gas initially present will solidify.</em> FALSE. Initially, Ar is present as a liquid.
<em>The final state of the substance is a solid.</em> FALSE.
<em>The sample is initially a liquid. One or more phase changes will occur.</em> TRUE. The sample is initially liquid and only one phase change will occur.
Answer:
You will need 12 moles of F2 if you want to make 8 moles of AlF3.
Explanation:
It takes 3 moles F2 to make 2 moles of AlF3 (this will be our mole ratio)
2 moles AlF3/3 moles F2 =8 moles AlF3/x moles AlF3.
x=12 moles AlF3