Answer:
Three half lives corresponds to (12)3 . So a 18 quantity of the original isotope is retained. And the percentage of quantity of a radioactive material that remains after 5 half-lives will be . ∴NN0×100=10032=3.125.
Food, Storage, and Structure
Answer:
Pyruvic acid: conjugate base
Lactic acid: conjugate base
Explanation:
The ratio of conjugate base to conjugate acid can be found using the Henderson-Hasselbalch equation when the pH and pKa are known.
pH = pKa + log([A⁻]/[HA])
The equation can be rearranged to solve for the ratio:
pH - pKa = log([A⁻]/[HA])
[A⁻]/[HA] = 10^(pH-pKa)
Now we can calculate the ratio for the pyruvic acid:
[A⁻]/[HA] = 10^(pH-pKa) = 10^(7.4 - 2.50) = 79433
[A⁻] = 79433[HA]
There is a much higher concentration of the conjugate base.
Similarly for lactic acid:
[A⁻]/[HA] = 10^(pH-pKa) = 10^(7.4 - 3.86) = 3467
[A⁻] = 3467[HA]
For lactic acid the conjugate base also dominates at pH 7.4
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An Endothermic Reaction occurs when the energy used to break the bonds in the reactants is greater than the energy given out when bonds are formed in the products
An Exothermic reaction is one that releases energy in the form of heat or light.
</span>Exothermic Reactions: Rust and Setting of Cement
Endothermic Reactions: Photosynthesis and evaporation.
One example of an endothermic reaction is Ice packs. The packs that deliver instant cooling when a seal inside is broken. It works by having water and ammonium nitrate in separate compartments and then when you break the seal between them they mix. The reaction is endothermic so it takes in heat from the surroundings so the pack become cold.
I hoped this helped you!
Answer:
Explanation:
The first thing we calculate are the moles: (50.0 g)/(20.0063 g/mol) =2.5 moles
Then we use the inverse formula for the molarity: (2.5 mol)/(12.0 M) = 0.208 L
My bad, I pressed the wrong button for answer!
