The activity of `1 g` radium is found to be 0.5. Calculate the half-life period of radium and the time required for the decay of `2 g` of radium to give `0.25 g` of radium (atomic mass off radium = 226).

Explanation

To solve the problem, we will break it down into two parts: calculating the half-life period of radium and determining the time required for the decay of 2 g of radium to give 0.25 g of radium.

### Part 1: Calculate the Half-Life Period of Radium

1. **Determine the Number of Atoms in 1 g of Radium:**
- The atomic mass of radium (Ra) is given as 226 g/mol.
- Using Avogadro's number (approximately \(6.022 \times 10^{23}\) atoms/mol), we can find the number of atoms in 1 g of radium.
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