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labwork [276]
3 years ago
9

Monica wrote the following observations about stars: "I observed a pattern of five stars at 8:00 p.m. and again at 9:00 p.m. The

pattern was in the exact same position both times. When I checked the same location again at 10:00 p.m., the pattern of five stars was not there." Choose the statement which corrects the error in Monica's observation.(2 points)
A.At 9:00 p.m., Monica would not be able to see the stars in the sky.
B.At 9:00 p.m., the pattern has moved to a different position in the sky.
C.At 10:00 p.m., only four of the five stars would be visible in the sky.
D.At 10:00 p.m., the pattern has moved to a different position in the sky.
Chemistry
2 answers:
stiv31 [10]3 years ago
8 0
The answer would be b
Mama L [17]3 years ago
6 0
I think it is C. Hope this helps
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1) From pV = nRT, n = pV / RT

Data:
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Now from a periodic table or a table you get that the molar mass of He is 4g/mol

So the numbers say that this gas is not pure helium , because its molar mass is more than double of the molar mass of helium gas.
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