B.
I hope this will help a bit (Forgive me of its wrong pls)
Well, figures for efficiency vary a lot, but according to Bicycling Science it’s lubrication that matters most – lubing a dry chain can add 5% to the efficiency.
More interestingly (and I hadn’t read this bit in the book before) it varys a lot depending on gear ratio – bottom gear (22-28) is 99% efficient, top gear (42-11) is 88%. That’s a big difference
The half-life of polonium-210, given that it decays from 98.3 micrograms to 12.3 micrograms in 414 days is 138 days
<h3>How to determine the number of half-lives </h3>
- Original amount (N₀) = 98.3 micrograms
- Amount remaining (N) = 12.3 micrograms
- Number of half-lives (n) =?
2ⁿ = N₀ / N
2ⁿ = 98.3 / 12.3
2ⁿ = 8
2ⁿ = 2³
n = 3
<h3>How to determine the half life </h3>
- Number of half-lives (n) = 3
- Time (t) = 414 days
- Half-life (t½) = ?
t½ = t / n
t½ = 414 / 3
t½ = 138 days
Learn more about half life:
brainly.com/question/26374513
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Answer:
Explanation:
I believe it is one because the energy is stored right before it falls
Answer:
A precipitate will be produced
Explanation:
The Ksp of AgBr is:
AgBr(s) → Ag⁺ + Br⁻
5.0x10⁻¹³ = [Ag⁺] Br⁻]
<em>Where [] are the concentrations in equilibrium of each ion.</em>
<em />
And if Q is:
Q = [Ag⁺] Br⁻]
<em>Where the concentrations are actual concentrations of each ion</em>
<em />
We can say:
IF Q >= Ksp, a precipitate will be produced
IF Q < Ksp, no precipitate will be produced.
the molar concentrations are:
[AgNO₃] = [Ag⁺] = 0.002M * (50mL / 100mL) = 0.001M
<em>Because 50mL is the volume of the AgNO₃ solution and 100mL the volume of the mixture of both solutions.</em>
[NaBr] = [Br⁻] = 0.002M * (50mL / 100mL) = 0.001M
Q = [0.001M] * [0.001M]
Q = 1x10⁻⁶
As Q > Ksp,
<h3>A precipitate will be produced</h3>