Answer:
\left \{ {{y=206} \atop {x=82}}Pb \right.
Explanation:
isotopes are various forms of same elements with different atomic number but different mass number.
Radioactivity is the emission of rays or particles from an atom to produce a new nuclei. There are various forms of radioactive emissions which are
- Alpha particle emission \left \{ {{y=4} \atop {x=2}}He \right.
- Beta particle emission \left \{ {{y=0} \atop {x=-1}}e \right.
- gamma radiation \left \{ {{y=0} \atop {x=0}}γ \right.
in the problem the product formed after radiation was Pb-206. isotopes of lead include Pb-204, Pb-206, Pb-207, Pb-208. they all have atomic number 82. which means the radiation cannot be ∝ or β since both radiations will alter the atomic number of the parent nucleus.
Only gamma radiation with \left \{ {{y=0} \atop {x=0}}γ \right. will produce a Pb-206 of atomic number 82 and mass number 206 , since gamma ray have 0 mass and has 0 atomic number.equation is shown below
\left \{ {{y=206} \atop {x=82}}Pb\right ⇒ \left \{ {{y=206} \atop {x=82}}Pb\right + \left \{ {{y=0} \atop {x=0}}γ\right.
Thus the atomic symbol is \left \{ {{y=206} \atop {x=82}}Pb\right
Physical because it is still H2O
Cooper cannot be broken down into a simpler substance since it is an element meaning it had its own atoms.
The condition at which the entropy of a pure solid will be zero is<span> when a substance is at absolute zero. Absolute zero is </span><span>the lowest temperature that is theoretically possible, at which the motion of particles which constitutes heat would be minimal. It is zero on the Kelvin scale, equivalent to −273.15°C.</span>
Answer:
the third option
Explanation:
The circuit is incomplete and broken, and the lights in the circuit do not shine.
An open circuit means an incomplete circuit.
The first option is wrong since the lights do not shine in an open circuit.
The second option is wrong since an open circuit is incomplete.
The fourth option is also wrong since an open circuit is broken or incomplete.
∴ The third option is correct.
