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musickatia [10]
3 years ago
9

Hurry PLEASE HELP!

Chemistry
1 answer:
avanturin [10]3 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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                                ΔTf<span> = (K</span>f)(<span>m)(i)
</span>where: 
ΔTf = change in freezing point = (Ti - Tf)
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Tf = freezing point of water with solute = ?
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i = ions in solution = 3

Computing for molality:
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When the concentration of D is decreasing by 0.10 M/s, how fast is the concentration of H increasing:

Given data = d[D]/dt = 0.10 M/s

-d[D] / 2dt  = d[H]/dt

d[H]/dt = 0.05 M/s

The concentration of H is increasing, half as fast as D decreases: 0.05 mol L–1.s–1

When the concentration of G is increasing by 0.20 M/s, how fast is the concentration of E decreasing:

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<span>C       -x                        x             x 
</span>---------------------------------------------
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