Answer:
1.13 moles Au
Explanation:
Moles Au = 6.80x10²³atoms / 6.023x10²³atoms/mole = 1.13 moles Au
The number of hours required : 37.2 hours
<h3>Further explanation</h3>
Given
⁴²K (potassium -42)
Required
The number of hours
Solution
The atomic nucleus can experience decay into 2 particles or more due to the instability of its atomic nucleus.
Usually, radioactive elements have an unstable atomic nucleus.
Based on Table N(attached), the half-life for ⁴²K is 12.4 hours, which means half of a sample of ⁴²K will decay in 12.4 hours
For three half-life periods :

For part of our orbit the northern half of Earth is tilted toward the Sun. This is summer in the northern hemisphere; there are longer periods of daylight, the Sun is higher in the sky, and the Sun's rays strike the surface more directly, giving us warmer temperatures.
Molar mass of LiBr (mm )= 86.845 g/mol
Molarity ( M ) = 4 M
Mass of solute ( m ) = 100 g
Volume ( V ) = in liters ?
V = m / mm * M
V = 100 / 86.845 * 4
V = 100 / 347.38
V = 0.2875 L
hope this helps!.