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charle [14.2K]
3 years ago
10

What do astronomers use to calculate the age of the universe? Select three options.

Chemistry
1 answer:
sasho [114]3 years ago
7 0

The answers are

The age of the oldest stars

How fast distant galaxies are moving away from us

Patterns of background radiation.

Explanation:

The Astronomers calculate the age of the universe by looking for oldest stars, and by measuring the rate of expansion of the universe and back to big bang.

The Astronomers used the techniques like the age of oldest stars, how fast the distant galaxies are moving away from us, patterns of background radiation and along with the Big Bang as reference point, they estimate that the universe may be approximately 12 billion years old.

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A___________ consists of a mixture of graphite powder (a form of carbon) and clay that is baked and hardened and encased in wood
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Answer:

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A compound is found to be 30.45% n and 69.55 % o by mass. if 1.63 g of this compound occupy 389 ml at 0.00°c and 775 mm hg, what
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1) mass composition

N: 30.45%
O: 69.55%
   -----------
   100.00%

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O: 69.55 / 16.00 = 4.346875

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=> n = pV / RT = (775/760) atm * 0.389 l / (0.0821 atm*l /K*mol * 273.15K)

=> n = 0.01769 moles

8) Find molar mass

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9) Find how many times the mass of the empirical formula is contained in the molar mass

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Answer: N2O4
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