Answer:
I know that the 100-mL graduated cylinders are always read to 1 decimal place.
I think for 50 mL graduated cylinders, it lets you measure volumes up to 50.0 mL to the nearest 0.1 or 0.2 mL, depending on your exact cylinder.
The question is incomplete, here is the complete question:
At elevated temperature, nitrogen dioxide decomposes to nitrogen oxide and oxygen gas

The reaction is second order for
with a rate constant of
at 300°C. If the initial [NO₂] is 0.260 M, it will take ________ s for the concentration to drop to 0.150 M
a) 1.01 b) 5.19 c) 0.299 d) 0.0880 e) 3.34
<u>Answer:</u> The time taken is 5.19 seconds
<u>Explanation:</u>
The integrated rate law equation for second order reaction follows:
![k=\frac{1}{t}\left (\frac{1}{[A]}-\frac{1}{[A]_o}\right)](https://tex.z-dn.net/?f=k%3D%5Cfrac%7B1%7D%7Bt%7D%5Cleft%20%28%5Cfrac%7B1%7D%7B%5BA%5D%7D-%5Cfrac%7B1%7D%7B%5BA%5D_o%7D%5Cright%29)
where,
k = rate constant = 
t = time taken = ?
[A] = concentration of substance after time 't' = 0.150 M
= Initial concentration = 0.260 M
Putting values in above equation, we get:

Hence, the time taken is 5.19 seconds
Answer:
-255.4 kJ
Explanation:
The free energy of a reversible reaction can be calculated by:
ΔG = (ΔG° + RTlnQ)*n
Where R is the gas constant (8.314x10⁻³ kJ/mol.K), T is the temperature in K, n is the number of moles of the products (n =1), and Q is the reaction quotient, which is calculated based on the multiplication of partial pressures by the partial pressure of the products elevated by their coefficient divide by the multiplication of the partial pressure of the reactants elevated by their coefficients.
C₂H₂(g) + 2H₂(g) ⇄ C₂H₆(g)
Q = pC₂H₆/[pC₂H₂ * (pH₂)²]
Q = 0.261/[8.58*(3.06)²]
Q = 3.2487x10⁻³
ΔG = -241.2 + 8.314x10⁻³x298*ln(3.2487x10⁻³)
ΔG = -255.4 kJ
pH value 1 represents a solution with the lowest OH⁻ion concentration.
<u>Explanation:</u>
pH is given by the expression as the negative logarithm to the base 10 of the concentration of hydrogen ions.
pH = -log₁₀[H⁺]
If the pH is lower than 7, pH < 7 then it is acidic
If the pH = 7, then it is neutral
If the pH > 7, then it is basic
If pH is 1 then the solution is showing mostly acidic character,which is least basic in its character.
So if the pH is 1, which is most acidic and least basic solution that is lowest OH⁻ ion concentration.
Answer:
52.54 %
Explanation:
Half life = 29 years
Where, k is rate constant
So,
The rate constant, k = 0.023902 hour⁻¹
From 1964 to 1991:
Time = 27 years
Using integrated rate law for first order kinetics as:
Where,
is the concentration at time t
is the initial concentration
So,
<u>The strontium-90 remains in the bone = 52.54 %</u>