All categories

3 years ago

Phosphorus-32 has a half life of 14.3 days. How many days will it take for a

Chemistry

1 answer:

olya-2409 [2.1K]3 years ago

3 0

It will take 42.9 days

<h3>Further explanation</h3>

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

t1/2=14.3 days

Nt/No=1/8

$\tt Nt=No(\dfrac{1}{2})^{T/t1/2}\\\\\dfrac{Nt}{No}=\dfrac{1}{2}^{T/t1/2}\\\\\dfrac{1}{8}=\dfrac{1}{2}^{T/t1/2}\\\\(\dfrac{1}{2})^3=\dfrac{1}{2}^{T/t1/2}\\\\3=T/14.3\rightarrow T=42.9~days$

You might be interested in

Since children of the first union/marriage have the trait the great- grandparents do not have the trait they must have been carr

stira [4]

Answer:

a.true

Explanation:

6 0

3 years ago

Read 2 more answers

During an investigation, similar glow sticks were placed in two beakers containing water at different temperatures. A record of

allochka39001 [22]

Answer:

i got you dawg just gimme one sec i'll get to you fr g

Explanation:

6 0

3 years ago

Read 2 more answers

How much energy must be removed from a 94.4 g sample of benzene (molar mass= 78.11 g/mol) at 322.0 K to solidify the sample and

Kay [80]

Answer : The energy removed must be, 29.4 kJ

Explanation :

The process involved in this problem are :

$(1):C_6H_6(l)(322K)\rightarrow C_6H_6(l)(279K)\\\\(2):C_6H_6(l)(279K)\rightarrow C_6H_6(s)(279K)\\\\(3):C_6H_6(s)(279K)\rightarrow C_6H_6(s)(205K)$

The expression used will be:

$Q=[m\times c_{p,l}\times (T_{final}-T_{initial})]+[m\times \Delta H_{fusion}]+[m\times c_{p,s}\times (T_{final}-T_{initial})]$

where,

$Q$ = heat released for the reaction = ?

m = mass of benzene = 94.4 g

$c_{p,s}$ = specific heat of solid benzene = $1.51J/g^oC=1.51J/g.K$

$c_{p,l}$ = specific heat of liquid benzene = $1.73J/g^oC=1.73J/g.K$

$\Delta H_{fusion}$ = enthalpy change for fusion = $-9.8kJ/mol=-\frac{9.8\times 1000J/mol}{78g/mol}=-125.6J/g$

Now put all the given values in the above expression, we get:

$Q=[94.4g\times 1.73J/g.K\times (279-322)K]+[94.4g\times -125.6J/g]+[94.4g\times 1.51J/g.K\times (205-279)K]$

$Q=-29427.312J=-29.4kJ$

Negative sign indicates that the heat is removed from the system.

Therefore, the energy removed must be, 29.4 kJ

3 0

3 years ago

What is the energy transformation in the following:

Tatiana [17]

They all have something to do with electricity

3 0

3 years ago

True/False: When a substance is heated, the change in energy causes the bonds between particles to become stronger.

Rzqust [24]

Answer:

false

Explanation:

the energy causes the bonds to become looser

5 0

3 years ago

Read 2 more answers