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Chemistry Item #5 What is the density (g /mL) of a sample of ethyl alcohol if a 63.3 g sample occupies 80.0 mL? A. 0.079 B. 0.79 C. 1.26 D. 12. www.upcatreview.com
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Chemistry Item #5What is the density (g /mL) of a
sample of ethyl alcohol if a 63.3 g sample occupies
80.0 mL?A. 0.079 B. 0.79 C. 1.26 D. 12.
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It’s not a hopeless case...
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You could follow two of our tips:
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hbb 2121
#31 Remove Extremes
For numerical items, remove the extremes (highest and lowest choice) and choose from the middle values.
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This tip should only be used when you have no idea on how to solve the
problem.
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Chemistry Item #5What is the density (g /mL) of a
sample of ethyl alcohol if a 63.3 g sample occupies
80.0 mL?A. 0.079 B. 0.79 C. 1.26 D. 12.6
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You’re now left with
two choices...
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hbb 2121
#25 Educated Guess
If you need to make a guess then it should be an educated guess. First, eliminate the answers that you know are wrong, then try your best to establish a basis for your choice.
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With the two choices
left,www.upcatreview.com
Chemistry Item #5What is the density (g /mL) of a
sample of ethyl alcohol if a 63.3 g sample occupies
80.0 mL?A. 0.079 B. 0.79 C. 1.26 D. 12.6
www.upcatreview.com
If you have the
knowledge...
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...that water is more
dense than most
alcohols.www.upcatreview.com
Perhaps because alcohols
evaporate faster than
water?www.upcatreview.com
And if you also have
the knowledge..
.www.upcatreview.com
...that the density of water is 1
g/mlwww.upcatreview.com
Then, choice C is also
eliminated...
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...simply because it’s higher than
1.www.upcatreview.com
Chemistry Item #5What is the density (g /mL) of a
sample of ethyl alcohol if a 63.3 g sample occupies
80.0 mL?A. 0.079 B. 0.79 C. 1.26 D. 12.6
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Thus, the answer is...
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B. 0.79
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To verify,
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Density = mass ÷ volume
Density = 63.3 ÷ 80.0=0.79125 ≈ 0.79
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