Question

1. Nuclear decay by alpha particle emission is more common in atoms of elements that:

Answer 1

Answer 1) Option a) have an atomic number greater than 83

Explanation : Nuclear decay by alpha particle emission is more common in atoms of elements that have an atomic number greater than 83. Nuclear reactions occurs with the elements which have mass number more than 200.

Answer 2) Option D) $He^{4}_{2}$

Explanation : In the given nuclear reaction of helium;

$He^{3}_{2} + He^{3}_{2} ----->$ $He^{4}_{2} + 2 P^{1}_{1}$

Two helium isotopes combines to give another helium isotope with emission of a proton (P).

Answer 3) Option D) The products are more radioactive than the reactants.

Explanation : The major drawback of a nuclear fission reaction to be used as an reliable energy source is that it usually produces the products which are found to be more radioactive than the reactants.

Answer 4) Option D) All of the above concerns.

Explanation : Nuclear reactions are usually very harmful in nature. It raises many concerns about the waste disposal that is generated from the reaction. It also requires safe operation for the working nuclear plants. It can also be misused for nuclear weapon proliferation. Hence, the answer is all of the above.

Answer 5) False.

Explanation : The energy output of the Sun and other stars is a result of fusion reactions among hydrogen nuclei. In fusion reactions usually additions takes place.

Answer 6) Option B) The "missing" mass has been converted to energy

Explanation : The total mass of a helium nucleus not equal to the mass of its individual parts because the missing mass has to be converted into energy.

Answer 7) Option A) less than the mass-energy of the products

Explanation : In a nuclear reaction, the mass-energy of the reactants is generally less than that of the mass-energy of the products because some energy has to be generated while the reaction is progressing.

Answer 8) Option D) $9.00 X 10^{17} J$

Explanation : The calculation of the mass of 10.0 kilograms is completely converted into energy.

$E = m X C^{2}$ formula can be used.

here m = 10 Kg and C = $3 X 10^{8} m/s$

E = 10 X $3 X 10^{8}$ = $9.00 X 10^{17} J$.

Answer 9) Option C) $3.60 X 10^{17} J$.

Explanation : For calculation of energy for mass of 4 Kg

we can use the Einstein's formula,

$E = m X C^{2}$

where m = 4 Kg and C = C = $3 X 10^{8} m/s$

E = 4 X $3 X 10^{8}$ = $3.60 X 10^{17} J$.

Answer 10) False.

Einstein's formula for the conversion of mass and energy, to find the energy, multiply the mass by the speed of light squared.

$E = m X C^{2}$