Answer is: concentration of hydrogenium ions is 9,54·10⁻⁵ M.
c(HNO₂) = 0,075 M.
c(NaNO₂) = 0,035 M.
Ka(HNO₂) = 4,5·10⁻⁵.
This is buffer solution, so use <span>Henderson–Hasselbalch equation:
pH = pKa + log(c(</span>NaNO₂) ÷ c(HNO₂)).
pH = -log(4,5·10⁻⁵) + log(0,035 M ÷ 0,075 M).
pH = 4,35 - 0,33.
pH = 4,02.
<span>[H</span>₃O⁺] = 10∧(-4,02).
<span>[H</span>₃O⁺] = 0,0000954 M = 9,54·10⁻⁵ M.
Answer:
6.32 moles of Fe
Explanation:
The given chemical equation is presented as follows;
2Fe + 3Cl₂ → 2FeCl₃
The mass of Cl₂ in the reaction = 336 grams
The molar mass of chlorine gas Cl₂ = 35.435 g/mol
The number of moles, n = Mass/(Molar mass)
The number of moles of Cl₂ in the reaction, n = 336 g/(35.435 g/mol) ≈ 9.842 moles
From the given reaction, 3 moles of Cl₂ react with 2 moles of Fe to produce 2 moles of FeCl₃
By the law of definite proportions, we have that 9.482 moles of Cl₂ will react with approximately 9.482 × 2/3 = 6.32 moles of Fe to produce approximately 6.32 moles of FeCl₃
Therefore, approximately 6.32 moles of Fe will be required to react with 336 grams of Cl₂.
3 minutes are left (16-13=3)
Critical Thinking Questions
1. Why do you think forensic scientists are so careful that the tests they do are sensitive, reproducible, and specific? What might happen if they were less careful about this?
They have to be careful to ensure as much accuracy as possible.
2.Which type of evidence do you think is most useful in an investigation? Why?
Physical evidence would probably be most important because it is the best way to connect someone directly with that crime.
3.Why do you think that forensic scientists continue to look for class characteristics given their limitations?
Class characteristics are good in court because it provides details of different aspects of the crime.
In order from the most likely to bind an oxygen to least likely;
3 bound o2, po2=100mmhg1 bound o2, po2=100mmhg3 bound o2, po2=40mmhg<span>1 bound o2, po2=40mmhg
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Haemoglobin is more likely to bind oxygen if its other oxygen binding sites have already bound to an oxygen molecule. The higher the partial pressure of oxygen in the blood also makes it more likely that the hemoglobin will bind oxygen.
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