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3 years ago

A 50.0g g sample of 16n decays to 12.5g in 14.4 seconds. What is its half life

1 answer:

8 0

T is amount after time t
Ao is initial amount 
t is time 
HL is half life 

log (At) = log [ Ao x (1/2)^(t/HL) ] 
log (At) = log Ao + log (1/2)^(t/HL) 
log (At) = log Ao + (t/HL) x log (1/2) 

( log At - log Ao) / log (1/2) = t / HL 
log (At/Ao) / log (1/2) = t / HL 

HL = t / [( log (At / Ao)) / log (1/2) ] 

HL = 14.4 s / [ ( log (12.5 / 50) / log (1/2) ] 

HL = 14.4 s / 2 = 7.2 seconds

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3 years ago

A container of carbon dioxide has a volume of 240 mL at a temperature of 22°C. If the pressure remains constant, what is the vol

astraxan [27]

Answer:

Volume of the $CO_{2}$ gas at 44°C is 258 ml.

Explanation

here,

using Charles' law ,

$\frac{V}{T} =\frac{v}{t}$

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Given - pressure is constant ,

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T= 22 + 273K = 295K (since converting celsius into kelvin that

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v = $\frac{240ml\times317K}{295K}$

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3 years ago

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LekaFEV [45]

Answer:

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Since the number of atoms of each element is written as a prefix before the main element, this means that the chemical formula of hexaboron tetrabromide will be B6Br4.

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2 years ago

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3 years ago