The answer is D. A positively charged sodium Ion and a negatively charged chlorine ion form an ionic bond.
Answer:
Explanation:
Let the number of half lives be x
<u>Solve this equation to find the value of x:</u>
- 125*(1/2)ˣ = 3.90625
- (0.5)ˣ = 3.90625 / 125
- (0.5)ˣ = 0.03125
- log (0.5)ˣ = log 0.03125
- x = log 0.03125 / log 0.5
- x = 5
Burning charcoal is a chemical reaction called combustion
# moles = mass (g) / Mr (relative atomic mass)
# moles = 458 / ((23*2)+32+(16*4)
# moles= 458 / 142 = 3.2253521126760...
= 3.23 moles