When organisms and plants died and sank to the bottom of swamps and oceans, brown soil-like materials called peat are formed. Over millions of years, the peat became covered with sand, clay and other minerals and the peat is converted into layers of sedimentary rocks. After a long time, different type of fossil fuels are formed.
<u>Ans: Acetic acid = 90.3 mM and Sodium acetate = 160 mM</u>
Given:
Acetic Acid/Sodium Acetate buffer of pH = 5.0
Let HA = acetic acid
A- = sodium acetate
Total concentration [HA] + [A-] = 250 mM ------(1)
pKa(acetic acid) = 4.75
Based on Henderson-Hasselbalch equation
pH = pKa + log[A-]/[HA]
[A-]/[HA] = 10^(pH-pKa) = 10^(5-4.75) = 10^0.25 = 1.77
[A-] = 1.77[HA] -----(2)
From (1) and (2)
[HA] + 1.77[HA] = 250 mM
[HA] = 250/2.77 = 90.25 mM
[A-] = 1.77(90.25) = 159.74 mM
Correct Answer: Option a. 6150.64 N
Weight (w) is defined as:
w = mg
So, first we need to find the mass (m) of the steel block using its volume and density.
Mass = Density x Volume
So,
m = 0.08 x 7840 = 627.2 g
Using value of m and g = 9.807, we get
w = 627.2 x 9.807 = 6150.95 Newtons
Therefore, option a is the correct answer.
The slight difference is because the value of g is rounded of to 3 decimal cases.
<u>Answer:</u> The number of moles of
is 0.05 moles.
<u>Explanation:</u>
To calculate the molarity of solution, we use the equation:

We are given:
Molarity of solution = 0.10 mol/L
Volume of solution = 1 L
Putting values in above equation, we get:

The chemical reaction for the ionization of sodium sulfate follows the equation:

By Stoichiometry of the reaction:
2 moles of sodium ions are produced by 1 mole of sodium sulfate
So, 0.10 moles of sodium ions will be produced by =
of sodium sulfate.
Hence, the number of moles of
is 0.05 moles.
The gas production not recognized as nitrate reduction is because <span>organisms that can ferment also produce gas. Therefore even if gas is produced on the tube, you can't tell if it's by fermentation or by nitrate reduction. I hope the answer helps. </span>