Answer:
41 g
Explanation:
We have a buffer formed by a weak acid (C₆H₅COOH) and its conjugate base (C₆H₅COO⁻ coming from NaC₆H₅COO). We can find the concentration of C₆H₅COO⁻ (and therefore of NaC₆H₅COO) using the Henderson-Hasselbach equation.
pH = pKa + log [C₆H₅COO⁻]/[C₆H₅COOH]
pH - pKa = log [C₆H₅COO⁻] - log [C₆H₅COOH]
log [C₆H₅COO⁻] = pH - pKa + log [C₆H₅COOH]
log [C₆H₅COO⁻] = 3.87 - (-log 6.5 × 10⁻⁵) + log 0.40
[C₆H₅COO⁻] = [NaC₆H₅COO] = 0.19 M
We can find the mass of NaC₆H₅COO using the following expression.
M = mass NaC₆H₅COO / molar mass NaC₆H₅COO × liters of solution
mass NaC₆H₅COO = M × molar mass NaC₆H₅COO × liters of solution
mass NaC₆H₅COO = 0.19 mol/L × 144.1032 g/mol × 1.5 L
mass NaC₆H₅COO = 41 g
Decomposition is a chemical reaction that breaks the reactant into two or more products. Moles of nitrogen gas 
in the cylinder is 1.63 moles.
<h3>What is the ideal gas equation?</h3>
The ideal gas equation states the relation of the hypothetical ideal gas according to the pressure, volume, temperature and moles of the gas. It is given by,
Where,
Pressure (P) = 2000 kPa
Volume (V) = 2L
Temperature (T) = 295 K
Gas constant (R)= 0.08206
Substituting values in the equation:
Therefore, 1.63 moles are produced.
Learn more about ideal gas equation here:
brainly.com/question/26720901
Answer:
8.10 hours.
Explanation:
You start with 500.0g.
After the first half-life, you have 250.0g.
After the second, you have 125.0g.
After the third, you have 62.50g.
Therefore, it takes three half-lives to decay to 62.50g.
Therefore, the elapsed time must be triple the length of one half-life.
24.3
3
=
8.10
, so it is 8.10 hours.
Explanation:
Answer:Student 2
Explanation:
Student 2 repeated the experiment several times with different seeds to make sure the experiment would come out with the same answers and was reliable, using the same area would make sure the environment wouldn't interfere. The other students didn't do all the things that student 2 needed for the experiment.
