Magnesium (Mg)
The reason for this is the reactivity of the listed metals. Gold and silver are extremely unreactive metals. It is because of this unreactive nature that they remain in good condition for long periods of time, and are preferred in jewelry. Copper, although more reactive than gold and silver, is still not reactive enough to react with HCl.
The only metal that will react is magnesium.
65. The atomic number is the number of protons in the atom.
Answer:
At the end of second half life 12.5 g will left
Explanation:
Given data:
Total Mass = 50 g
Half lives = 2
Mass remain at the end = ?
Solution:
At time zero = 50 g
At 1st half life = 50 g /2 = 25 g
At second half life = 25 g/2 = 12.5 g
So at the end of second half life 12.5 g will left.
2n+a is the simplified expression