Half-life is a time in which the concentration of the substance gets reduced to 50% of the initial concentration. The number of tritium that will be left after 51 years is 0.624 kg.
<h3>What is an isotope?</h3>
Isotopes are chemical substances that have the same atomic number but different atomic mass because they have a different number of neutrons in the nuclei.
The half-life of the isotope, tritium is 12.3 years. Assuming we have 11 kg of substance and a number of years 51 years.

Therefore, the number of tritium that will be left after 51 years is 0.624 kg.
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Answer:
This isotope has 59 electrons giving it a charge of -2.
Explanation:
To find this we have to understand isotope relates to the mass of the nucleus. This isotope has 59 electrons to counter the protons and give it a negative charge.
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