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musickatia [10]
2 years ago
9

Hurry PLEASE HELP!

Chemistry
1 answer:
avanturin [10]2 years ago
7 0

B. 11,540

<h3>Further explanation </h3>

The atomic nucleus can experience decay into 2 particles or more due to the instability of its atomic nucleus.  

Usually radioactive elements have an unstable atomic nucleus.  

General formulas used in decay:  

\large{\boxed{\bold{N_t=N_0(\dfrac{1}{2})^{t/t\frac{1}{2} }}}

T = duration of decay  

t 1/2 = half-life  

N₀ = the number of initial radioactive atoms  

Nt = the number of radioactive atoms left after decaying during T time  

Nt=25 g

No=100 g

t1/2=5770 years

\tt 25=100\dfrac{1}{2}^{T/5770}\\\\\dfrac{1}{4}=\dfrac{1}{2}^{T/5770}\\\\2=T/5770\rightarrowT=11540~years

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Answer:

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Answer:

Its final temperature is 25.8 °C

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When a body transmits heat there is another that receives it. This is the principle of the calorimeter. Then the heat released by the compound will be equal to the heat obtained by the calorimeter.

In this case, you know:

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Replacing:

14,000 J= 3.55 \frac{J}{g*C}*1200 g*(Tfinal-22.5C)

Solving:

\frac{14,000J}{3.55\frac{J}{g*C} *1200 g} =T final - 22.5C

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