We have to get the stable atom formed after positron emission from Terbium-147.
The stable atom is (D) ₆₄Gd¹⁴⁷.
Positron is radioactive decay. Positron is a type of beta particle β⁺.
Positron emission decreases proton number relative to neutron number, positron decay results in nuclear transmutation, changing an atom of one chemical element with an atomic number that is less by one.
Terbium on positron emission produces Gadolinium with one atomic number less than Terbium. So, the positron emission reaction is as shown below:
Tb¹⁴⁷→ ₆₄Gd¹⁴⁷ + ₁e⁰
They are called Cargo Shorts.
I think the answer is B.
I know the answer cant be A because a lot of metal that is new can be shiny.
C is incorrect because malleable means that it can be permanently bent out of shape ( which metal can be )
D is incorrect because a lot of metal can conduct electricity for example copper and brass can both conduct electricity
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Answer:
a)CH₄, BH₃, and CCl₄
Explanation:
<u>London dispersion forces:-
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The bond for example, in the molecule is F-F, which is non-polar in nature because the two fluorine atoms have same electronegativity values.
The intermolecular force acting in the molecule are induced dipole-dipole forces or London Dispersion forces / van der Waals forces which are the weakest intermolecular force.
Out of the given options, H₂O , NH₃ exhibits hydrogen bonding which is:-
<u>Hydrogen bonding:-
</u>
Hydrogen bonding is a special type of the dipole-dipole interaction and it occurs between hydrogen atom that is bonded to highly electronegative atom which is either fluorine, oxygen or nitrogen atom.
Thus option B and C rules out.
<u>Hence, the correct option which represents the molecules which would exhibit only London forces is:- a)CH₄, BH₃, and CCl₄</u>
