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2 years ago

In 36 hours the amount of radioactive substance has reduced from 80 mg to 10 mg. What is the half-life of this isotope?

1 answer:

6 0

Half-life refers to the time taken for half of the atoms in a radioactive substance to decay. Therefore in 1 half-life the 80 mg of substance will reduce to 40 mg. In another half-life it will reduce from 40 mg to 20 mg, then in a third half-life from 20 mg to 10 mg. Therefore the half-life is equal to the total time taken to decay from 80 mg to 10 mg divided by 3:
t(1/2) = 36 hours / 3 = 12 hours.

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Determine how many moles are present in 0.23kg of SO(2)

Rama09 [41]

Answer:

3.59 moles

Explanation:

Hopefully this helps! :)

Mark as brainliest if right!

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3 years ago

Answer True or False for each of the following statements. (a) The carburization surface was maintained at slightly less than 0.

fomenos

Answer:

verdadero/a

falso/b

verdadero/c

Explanation:

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2 years ago

Argon (Ar) and helium (He) are initially in separate compartments of a container at 25°C. The

love history [14]

Answer:

(a) $V_B=11.68L$

(b) $x_{He}=0.533$

Explanation:

Hello,

In this case, since the both gases behave ideally, with the given information we can compute the moles of He in A:

$n_A=\frac{0.082\frac{atm*L}{mol*K}*298K}{1.974 atm*6.00L}=2.063mol$

Thus, since the final pressure is 3.60 bar, we can write:

$P=x_{Ar}P_A+x_{He}P_B\\\\P=\frac{n_{Ar}}{n_{Ar}+n_{He}} P_A+\frac{n_{He}}{n_{Ar}+n_{He}} P_B\\\\3.60bar=\frac{2.063mol}{2.063mol+n_{He}} *2.00bar+\frac{n_{He}}{2.063mol+n_{He}} *5.00bar$

The moles of helium could be computed via solver as:

$n_{He}=2.358mol$

Or algebraically:

$3.60bar=\frac{1}{2.063mol+n_{He}} *(4.0126+5.00*n_{He})\\\\7.314+3.60n_{He}=4.013+5.00*n_{He}\\\\7.314-4.013=5.00*n_{He}-3.60n_{He}\\\\n_{He}=\frac{3.3}{1.4}=2.358mol$

In such a way, the volume of the compartment B is:

$V_B=\frac{n_{He}RT}{P_B}=\frac{2.358mol*0.082\frac{atm*L}{mol*K}*298.15K}{4.935atm}\\ \\V_B=11.68L$

Finally, he mole fraction of He is:

$x_{He}=\frac{2.358}{2.358+2.063}\\ \\x_{He}=0.533$

Regards.

8 0

2 years ago

g Alkenes and alkynes are called unsaturated compounds because ________. they have fewer hydrogen atoms attached to the carbon c

Firdavs [7]

Answer:

They have fewer hydrogen atoms attached to the carbon chain than alkanes

Explanation:

Let's compare ethane (an alkane) with ethene (an alkene) and ethyne (an alkyne):

Ethane's formula is C₂H₄, while ethene's is C₂H₄ and ethyne's C₂H₂.

As you can see, alkenes and alkynes have fewer hydrogen atoms attached to the carbon chain due to them having multiple bonds between the carbon atoms.

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3 years ago

The symbol, Mg(s), shows magnesium in its standard state. True or False?

puteri [66]

Answer:

True?

Explanation:

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3 years ago