Question

Problem 1	Concept:	Elementary Particles		0	Not finished!
Level: Basic
Emission of which particle below will decrease the mass number by 1, but have no affect on the atomic number?
	a gamma photon
	a neutron
	a beta particle
	an alpha particle

Problem 2	Concept:	Nuclear reactions		0	Not finished!
Level: Basic
When 59Cu undergoes positron emission, what is the immediate nuclear product?
	59Zn
	58Cu
	59Ni
	58Ni

Problem 3	Concept:	Radioactivity		0	Not finished!
Level: Basic
Which of the nuclides is most likely radioactive?
	39K
	218At
	28Si
	2H

Problem 4	Concept:	Band of Stability		0	Not finished!
Level: Basic
Which of the unstable nuclides below will result in electron capture or positron emission during radioactive decay? 192Os is the most stable isotope of this element.
	194Os
	193Os
	195Os
	172Os

Problem 5	Concept:	Half-life and rate constant		0	Not finished!
Level: Basic
How much time in hours would it take for a 2.649 g sample of 18F to decay to a mass of 1.465 g if it has a half-life of 6.5880e+3 s.
	Enter answer here:

Problem 6	Concept:	Age of material		0	Not finished!
Level: Intermediate
A rock containing 238U and 206Pb was examined to determine its approximate age. The sample of a rock contained 1.611 g of 206Pb and 10.67 g 238U. Assuming no lead was originally present and that all lead formed from 238U remained in the rock, what is the age of the rock (in years)? The half-life of 238U is 4.500e+9 yr.
	Enter answer here:

Problem 7	Concept:	Nuclear Binding Energies		0	Not finished!
Level: Basic
How many kJ of energy are released to form one mole of 87Rb from protons and neutrons if the atom has a mass of 86.9091870 amu? Please remember to include the mass of electrons in the calculation. Given the mass of a proton is 1.007825 amu

Answer 1

Following is the - complete Answer -&- Explanation: for the first four questions ( i.e. Q.1 - to - Q.4 ) , of the given ....: Question Set - in.........Typed Format...

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Question - (1): Answer -&- Explanation:

Answer:

Option - (b): a Neutron

Explanation:

Following is the complete Explanation, for the above Answer, in....Typed Format...

We know, with a neutron emission, the atom of a radioactive element , loses one neutron ONLY, which doesn't change the number of protons, of the atom. Thus, even after the emission of a neutron, the atomic number, of the atom remains constant. But , with since with emission of a neutron, the atom loses a neutron, the mass number , of the atom, changes ONLY...

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Question - (2): Answer -&- Explanation:

Answer:

Option - ( C ) :   ⁵⁹Ni

Explanation:

Following is the complete Explanation - for the above Answer, in.....Typed Format.....

  Following is the complete nuclear reaction, of positron decay / emission of : Copper ( Cu )

⁵⁹Cu₂₉   ⁵⁹Ni₂₈ + e⁺( positron ) + v_e( emission of energy )

i.e. as we can see above, due to positron emission, the atomic number of copper ( i.e. Cu ) , decreases, by one, and the mass number , of copper ( Cu ) , remains the same. Thus positron emission of copper leads to the creation of ----

--- ⁵⁹Ni₂₈

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Question - (3): Answer -&- Explanation:

Answer:

Option - (b) : ²¹⁸At

Explanation:

The isotope of Astatine: ²¹⁸At, will be radioactive , because this nuclide is not stable, and it undergoes , alpha ( ) and beta ( ) decay, --- respectively, and is therefore Radioactive nuclide.

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Question - (4): Answer -&- Explanation:

Answer:

Option - ( d ) :   ¹⁷²Os

Explanation:

Since, this radioactive isotope of osmium - i.e.  ¹⁷²Os, goes through radioactive decay - of positron emission

( ⁺decay ) ---- this will be our Answer.....

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