Answer:
0.89M
Explanation:
Because moles of solute do not change, we can write
M1V1 = M2V2
M - molarity, V - volume of solution
2.0M*200mL = M2*450mL
M2 = 0.89 M
Answer:
67.6 years is the time the isotope take to decay from 0.900g to 0.170g
Explanation:
The radioactive decay follows first order law:
Ln [A] = -kt + ln[A]₀
<em>Where [A] is concentration after time t,</em>
<em>k is decay constant:</em>
<em>k = ln 2 / t(1/2)</em>
<em>k = ln2 / 28.1 years</em>
<em>k = 0.02467 years⁻¹</em>
<em>[A]₀ = Initial concentration.</em>
<em />
We can replace concentration and use the mass of the isotope:
Ln [A] = -kt + ln[A]₀
Ln [0.170g] = -0.02467 years⁻¹t + ln[0.900g]
-1.667 = -0.02467 years⁻¹t
t =
<h3>67.6 years is the time the isotope take to decay from 0.900g to 0.170g</h3>
Oxygen and water
Plants release water through osmosis and oxygen through stomata
<span>When 1 mol of glucose is burned, 2802.5 KJ of energy is released.
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