Answer:

Explanation:
N = Final mass of atom = 125 g
= Initial mass of atom = 16000 g
t = Time taken = 163.24 days
= Half life
We have the relation

The half life of the atom is
.
Moles of ammonia
- Given mass/Molar mass
- 230/17
- 13.5mol
1mol requires 5.66KJ energy
13.5mol requires
A chemical change is the answer
Answer:
Explanation:
Many elements have similar properties. This can be seen in how periodic table is arranged. The vertical columns on the periodic table are called groups or families because of their similar chemical behavior. All the members of a family of elements have the same number of valence electrons and similar chemical properties.
For eg: Lithium, Sodium, and Potassium fall under group one in periodic table. These elements exhibit similar properties such as being extremely reactive.
Answer:
• The closing of the frontier
Explanation:
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