A.) half - life of a radioactive substance is defined as the time during which concentration of the substance becomes half the initial value.
The new volume : 0.07 L
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Further explanation</h3>
Boyle's Law
At a constant temperature, the gas volume is inversely proportional to the pressure applied

P₁=1 atm
V₁=0.39 L
P₂=5.6 atm

Answer:
Those that “prefer” A charge; the Halogens and Chalcogens are good examples - Halogen MEANS salt forming, and even organic compounds can form salts; look up “tropylium ion”.
Explanation:
Answer: B
Explanation: molarity = concentration c= n/V = 0.5 mol/ 0.05 l = 10 mol/l