Question

In: Chemistry

1. Select the statement that is NOT true about venting during an extraction. A.The separatory funnel...

1. Select the statement that is NOT true about venting during an extraction.

A.The separatory funnel stem should not be pointed towards any person while venting.

B. The stopper must be held in place while venting.

C.The stopper must be held in place while venting.

D.The separatory funnel must be inverted before venting.

2. Select the general rule that is true about performing an extraction.

A. The top layer of the extraction contains the desired product.

B. All liquid layers should be saved until it is known which layer contains the desired product.

C. To avoid the formation of an emulsion, the bottom liquid layer should be separated from the top layer as quickly as possible.

D. During an extraction, the separatory funnel should never be inverted more than 10 times.

3. An emulsion forms during an extraction. Select the best course of action to quickly break the emulsion.

A. Shake the separatory funnel vigorously.

B. Dispose of the emulsion and restart the experiment.

C.Allow the emulsion to sit for 1–2 hours.

D. Add sodium chloride.

Expert Solution

1. Select the statement that is NOT true about venting during an extraction.

A.The separatory funnel stem should not be pointed towards any person while venting.: True

B. The stopper must be held in place while venting.True

C.The stopper must be held in place while venting.True

D.The separatory funnel must be inverted before venting.True

The actual false statement is: The stopcock must be closed.

2. Select the general rule that is true about performing an extraction.

A. The top layer of the extraction contains the desired product.Not true (it can be in be in any layer depeding upon solubility)

B. All liquid layers should be saved until it is known which layer contains the desired product" True

C. To avoid the formation of an emulsion, the bottom liquid layer should be separated from the top layer as quickly as possible.: Not true (we have to wait till complete separation)

D. During an extraction, the separatory funnel should never be inverted more than 10 times Not true

3. An emulsion forms during an extraction. Select the best course of action to quickly break the emulsion.

A. Shake the separatory funnel vigorously.: Not true (it will not break emulsion)

B. Dispose of the emulsion and restart the experiment. (Not true)

C.Allow the emulsion to sit for 1–2 hours. (not true)

D. Add sodium chloride. (True)

queen_honey_blossom answered 2 years ago

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