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DerKrebs [107]
2 years ago
14

the half life for strontium-90 is 29 years. how many half-lives did the sample go through at the end of 87 year​

Chemistry
2 answers:
tatuchka [14]2 years ago
6 0

= 87 : 29

= 3 half lives

Nesterboy [21]2 years ago
4 0
90 divided by 29 x 87 = 290
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In a room full of air, the air is mainly composed of Nitrogen and Oxygen molecules (both at room temperature). Find (to two sign
zloy xaker [14]

Explanation:

Expression for the v_{rms} speed is as follows.

            v_{rms} = \sqrt{\frac{3kT}{M}}

where,   v_{rms} = root mean square speed

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As the molecular weight of oxygen is 0.031 kg/mol and R = 8.314 J/mol K. Hence, we will calculate the value of v_{rms} as follows.

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                            = \sqrt{\frac{3 \times 8.314 J/mol K \times 309.02 K}{0.031 kg/mol}}

                            = 498.5 m/s

Hence, v_{rms} for oxygen atom is 498.5 m/s.

For nitrogen atom, the molecular weight is 0.028 kg/mol. Hence, we will calculate its v_{rms} speed as follows.

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T
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Explanation:

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3 years ago
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I'm pretty sure the answer is 0.833 atm.

Hope I helped! <3

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3 years ago
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