Answer:
Percentage Yield is given as,
%age Yield = Actual Yield / Theoretical Yield × 100
This shows that the %age yield is directly depending upon the actual yield. And most of the time the percentage yield is less than 100 % because of the following factors.
Impure Starting Materials:
If the starting materials (reactants) are not pure then reaction will not completely form the desired product. Different by products will form which will decrease the %age yield.
Incomplete Reactions:
Not all reactions go to completion. In many reactions the starting material after some time stops forming the product due to different conditions. Some reactions attain equilibrium and stop increasing the amount of product. While, in some reactions a by products (like water) formed often react with the product to give a reverse reactions. Hence, the chemistry of reactions also causes the decrease in %age yield.
Handling:
Another major reason for decrease in yield is handling the product. Always some of the product is lost during the workup of the reaction like, taking TLC, doing solvent extraction, doing column chromatography, taking characterization spectrums. So, we can conclude that the %age yield will always be less than 100%.
Answer:
3.2 × 10⁻⁸
Explanation:
Let's consider the solution of magnesium carbonate.
MgCO₃ ⇄ Mg²⁺(aq) + CO₃²⁻(aq)
We can relate the molar solubility (S) with the solubility product (Ksp) using an ICE chart.
MgCO₃ ⇄ Mg²⁺(aq) + CO₃²⁻(aq)
I 0 0
C +S +S
E S S
The Ksp is:
Ksp = [Mg²⁺] × [CO₃²⁻] = S × S = S² = (1.8 × 10⁻⁴)² = 3.2 × 10⁻⁸
Answer:
It is used as a catalyst.
Answer:
Explanation:
To convert from moles to grams, the molar mass must be used.
1. Find Molar Mass
The compound is iron (III) chloride: FeCl₃
First, find the molar masses of the individual elements in the compound: iron (Fe) and chlorine (Cl).
There are 3 atoms of chlorine, denoted by the subscript after Cl. Multiply the molar mass of chlorine by 3 and add iron's molar mass.
- FeCl₃: 3(35.45 g/mol)+(55.84 g/mol)=162.19 g/mol
This number tells us the grams of FeCl₃ in 1 mole.
2. Calculate Moles
Use the number as a ratio.
Multiply by the given number of grams, 345.0.
Flip the fraction so the grams of FeCl₃ will cancel.
Divide.
3. Round
The original measurement of grams, 345.0, has 4 significant figures. We must round our answer to 4 sig figs.
For the answer we calculated, that is the thousandth place.
The 1 in the ten thousandth place tells us to leave the 7 in the thousandth place.
There are about <u>2.127 mole</u>s of iron (III) chloride in 345.0 grams.
