Answer:
Percent yield of reaction is 75%.
Explanation:
Given data:
Moles of A = 2.0 mol
Moles of B = 4.0 mol
Moles of C formed = 1.8 mol
Percent yield of reaction = ?
Solution:
Chemical equation:
2A + 5B → 3C + D
We will compare the moles of A and B with C from balance chemical equation.
A : C
2 : 3
B : C
5 : 3
4 : 3/5×4 = 2.4 mol
Number of moles of C formed by 4 moles B are less thus B is limiting reactant and will limit the yield of C.
Percent yield:
Percent yield = actual yield /theoretical yield × 100
Percent yield = 1.8 mol / 2.4 × 100
Percent yield =75%
An mL is also equivalent to cm³, signifying that 140 mL is equivalent to 140 cm³. The mass of ethanol is calculated by multiplying the density by the volume.
mass = (140 cm³)(0.789 g/cm³)
mass = 110.46 g
Then, calculate the number of moles of ethanol by dividing the mass by the molar mass of ethanol equal to 46.07 g/mol.
number of moles = (110.46 g/ 46.07 g/mol) = 2.4 mol
Then, multiply the number of moles by the Avogadro's number.
2.4 mol (6.022 x 10²³)
<em> number of molecules = 1.445 x 10²⁴</em>
The relative humidity of the air is the ratio of the actual amount of moisture in the air to the fully saturated amount. There for the answer is 33.1% or 3.3g/kg
Answer: There are several ways. The first that comes to mind is a pH meter. A pH electrode Is lowered into the solution, and (Assuming) the pH Meter has been properly calibrated, and the temperature of the solution is set to the calibration of the Meter, the pH can be read directly from an analogue scale or digital readout. Below 7 is acidic, 7 is Neutral, (like Pure Water), and over 7 is Alkaline, or Basic.
A useful, but less accurate method is the use of any number of “pH Indicator Solutions”, which are essentially a type of various colored dyes that change color within differing pH ranges. Usually, if the pH is unknown, a small amount of solution is removed from the container and tested separately - in a “well plate”, or similar method.
These types of dyes, or Indicator Solutions, can be dried upon strips of “pH indicator Paper”, which, depending upon the type can be very useful when carrying out more precisely arrived at pH tests like Titration.
Just to see if a solution is “Acid” or “Base”, Litmus paper is used; “a Red color shows Acidity, and a Blue color, a Base”; ergo, “An Acid Solution will turn Litmus Paper, Red”.
Answer:
[H+] = 4.365x10⁻¹¹
Explanation:
The pH is a measurement widely used in chemistry. Is used in quality control to determine if a product is good for human or pet consumption. The equation to obtain the pH is:
pH = -log [H+]
To solve [H+]:
10^pH = -[H+]
10^-pH = -[H+]
In the problem:
10^-10.36 = -[H+]
<h3>[H+] = 4.365x10⁻¹¹</h3>
