(a) Write the complete \(\beta^{-}\) decay equation for \(^{90} \mathrm{Sr}\), a major waste product of nuclear reactors. (b) Find the energy released in the decay.

Short Answer

Expert verified
The complete β⁻ decay equation for Strontium-90 is \(^{90}_{38}Sr => ^{90}_{39}Y + ^0_{-1}e + \bar{v}_e\). The energy released can be calculated using the mass-energy conservation principle and would be E=Δm.c², where Δm is the mass difference before and after the decay and c is the speed of light.

Step by step solution

01

Understand Beta Decay

Beta decay is a type of radioactive decay in which a beta particle, which is an electron or a positron, is emitted. In the case of β⁻ decay, a neutron in the nucleus transforms into a proton, an electron, and an electron antineutrino. This increases the atomic number by 1.
02

Write the Beta Decay Equation for Sr-90

The β⁻ decay equation for Strontium-90 can be written as follows: \(^{90}_{38}Sr => ^{90}_{39}Y + ^0_{-1}e + \bar{v}_e\) where \(^{90}_{38}Sr\) is Strontium-90, \(^{90}_{39}Y\) is Yttrium-90, ^0_{-1}e is the beta particle (electron), and \(\bar{v}_e\) is the electron antineutrino.
03

Calculate the Energy Released in the Decay

The energy released in the decay can be calculated using the principle of conservation of mass-energy, which states that the total energy before and after the decay remains the same. First, the difference in mass before and after the decay (Δm) needs to be calculated. This is given by Δm = (mass of \(^{90}_{38}Sr\)) - ((mass of \(^{90}_{39}Y\)) + mass of electron)). Then, the energy (E) released is given by the equation E=Δm.c², where c is the speed of light. The masses must be in equivalent energy units (such as MeV/c² or kg if c is given in m/s) while calculating Δm.

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