As the metal rusts it expands increasing its mass therefore increasing the weight.
Boron trifluoride is the correct name for compound BF3
Sodium-25 after 3 minutes : 1.0625 mg
<h3>Further explanation</h3>
General formulas used in decay:

T = duration of decay
t 1/2 = half-life
N₀ = the number of initial radioactive atoms
Nt = the number of radioactive atoms left after decaying during T time
<h3 />
No=8 mg
t1/2=60 s
T=3 min=180 s

Answer:
5.35m H2O2 x 34.02g/1m H2O2 = 182g H2O2
Explanation:
Systems can exist in three ways as open systems, closed systems, and isolated systems. The main difference between open and closed system is that in an open system, matter can be exchanged with the surrounding whereas, in a closed system, matter cannot be exchanged with the surrounding.
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