<span>Selenium (se)
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The answer is isotopes<span>. Isotopes are different kind of atoms of the same element. Elements are identified by the number of protons in the nucleus (atomic number), so all the aoms of uranium have the same number of protons. When one element can have atoms with different number of neutrons (which is pretty normal) the different forms are called isotopes. So, isotopes are different versions of the same element which differentiate from each other in the number of neutrons.</span>
the system is in constant temperature
so it follows Boyle's law
i.e.P1V1=P2P2
where P1=initial pressure=788 tour
P2=final pressure= ?
V1=initial volume=235 ml
V2=final volume=0.115 ml
You can use the equation f(t) = 5*(1/2)^(t/8.02)
Then plug in 6.01 for time.There remains 2.97 mg in the sample.
