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Unit - 4.3 Chemical Bond, Valency and Radioactivity — CHEMISTRY STD 8 — Question

ICSE BoardEnglish MediumSTD 8CHEMISTRYUnit - 4.3 Chemical Bond, Valency and Radioactivity2 Marks
Question
What do you understand by the following terms:
(b) Radioactive substance
✓

Answer

The energy or particles emitted during radioactive decay are referred to as radiation.
- The rate at which a material emits radiation is referred to as its radioactivity.
- The number of disintegrations per unit of time is used to determine the activity of a sample of radioactive material.
- There are a total of 38 radioactive elements in the universe.
- Examples are Radium: Polonium and barium are some radioactive substances.

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