RENDEMEN IN CHEMICAL REACTIONS
In chemistry, the chemical yield, the yield of the reaction, or
only the rendement refers to the amount of reaction product produced in the
chemical reaction. Absolute rendement can be written as weight in grams or in
moles (molar yield). The relative yield used as a calculation of the
effectiveness of the procedure is calculated by dividing the amount of product
obtained in moles by the theoretical yield in moles:
To obtain a percentage yield, multiply the fractional yield by
100%.
One or more reactants in chemical reactions are often used
redundantly. The theoretical rendement is calculated based on the number of
moles of the limiting reagent. For this calculation, it is usually assumed that
there is only one reaction involved
The yield of a particular product is the maximum result obtained if
the reactants only produce the product without side reactions while the real
rendement is the number of products actually obtained in an experiment
Rendement percentage = actual yield : theoritical rendement x 100%
1.
Stoichiometry
Stoichiometry
is a chemical calculation involving the kuntitatif relationship of substances
involved in the reaction, both reagents and reaction products
The
theoretical results are calculated quantities of balanced chemical equations or
how many products are obtained based on stoichiometric calculations
The
real or actual result is the number of tangible results that are obviously
produced in a chemical reaction or beraoa many products obtained after the
reaction is complete
The
efficiency of a chemical reaction can be determined by percent yield
calculation or percentage yield: Percent yield = (real result / theoretical
result) x 100%
The
ideal chemical yield value (theoretical rendement) is 100%, a value highly
unlikely to be achieved in its practice. Calculate the percent of rendemen that
is by using the following equations percent rendemen = weight yield / weight of
yield divided by the sample weight multiplied by 100%
Example :
a.
If the reaction between 6 grams of ethane C2H6
(Mr = 30) with 7.1 grams of Cl2 (Mr = 71) yields 5.16 grams of C2H6Cl
(Mr = 64.5) then the percentage of ethylchloride yield is?
Answer:
In
this case we are required to calculate% C2H6Cl, so let's
compare facts and theories:
Fact:
The
resulting C2H6Cl period = 5.16 grams
C2H6CL = mass/mr = 5,16/64,5 =0,08 mol
Theory :
We look for the
C2H6Cl period that results from the reaction
n C2H6 = Mass/Mr = 6/30 = 0,2 mol
n Cl2 = mass/ mr = 7,1 / 71 = 0,1 mol
2 C2H6 + Cl2 >>> 2C2H5CL + H2
Mula-mula 0,2
0,1 - -
Bereaksi 0,2 0,1 0,2
0,1
Sisa - - 0,2 0,1
Theoretically C2H5Cl
resulting from the reaction is 0.2 mol
% C2H5CL = actual /theoritical x 100%
= 0,08/0,2 X 100% = 40%
b.
Commercial
acetic acid (97% C2H4O2) reacted with excess
PCl5 will produce acetyl chloride (C2H3OCl).
If the acetyl chloride produced is 75 g and the reaction efficiency (rendement)
78.2%, then the amount of acetic acid reacted is ..
Answer:
97% = 0.97
78.2% = 0.782
Rendement fraksional = actual yield : theoritical rendement
0.782 = 75 /
theoretical rendement
Theoretical
rendement = 75 / 0.782
Theoretical
rendement = 95.9 gr
The resulting
theoretical yield of acetic acid was 95.9 gr
Percent of
acetic acid = 97% = 0.97
Mean, acetic
acid = 05.9 x 0.97
Acetic acid =
93 grams
Thus, the amount of acetic acid
treated was 93 grams
Tell me more about rendemen in chemical reactions?
BalasHapusRendement in aromatic compounds is the ratio of the quantity (quantity) of oil produced from the extraction of aromatic plants. Rendemen use percent unit (%). The higher the yield value indicates that the value of the oil produced is more benyak.
HapusIncreasing the yield or the ratio of the amount of oil produced can be done with two approaches. One or more reactants in chemical reactions are often used redundantly. The theoretical rendement is calculated based on the number of moles of the limiting reagent. For this calculation, it is usually assumed that there is only one reaction involved
The yield of a particular product is the maximum result of the reactants
Why in chemistry is there a rendmen?
BalasHapusBecause chemical reaction is a process whereby new substances, the reaction product, are formed from some of the original substances, called reactions. Usually a chemical reaction is accompanied by physical events, such as discoloration, sediment formation, or gas generation. Symbols expressing a chemical reaction are called chemical equations. If the chemical compounds bind and can react then the chemical compounds will convert reagents into products, otherwise if the chemical elements can not bind then will not form the product
HapusWhat factors affect the outcome ?
BalasHapusThe factors that affect the product vary depending on what kind of reaction the product is produced. For example at the rate of reaction of factors that will affect the product are:
Hapus1. concentration
2. surface area
3. pressure
4. temperature
5. catalyst
But on average some of the reactions tend to be influenced by the 5 factors
What is a side reaction? Please provide an explanation.
BalasHapusSide reactions (Reactions In addition to plural) (chemical) radical reactions are added to both sides of the two or three bonds. The two most common types of side reactions are the elimination and rearrangement of carbocation. If this reaction is carried out in a warm or hot state (which increases entropy), E1 elimination reactions will dominate, resulting in the formation of alkenes. Even if the reaction is carried out in low temperatures, small amounts of alkenes may also form. Attempts to conduct SN1 reactions using strongly alkaline nucleophiles such as hydroxide ions or methoxides will also result in the formation of alkenes via the E2 elimination reaction, even more so when the reaction is heated. In addition, if the intermediate carbocation can be rearranged into a more stable carbocation, it will provide a more stable reaction result from a carbocation than a simple substitution reaction
HapusPlease give example of rendemen in everyday life ??
BalasHapusIn chemistry, the chemical yield, the yield of the reaction, or only the rendement refers to the amount of reaction product produced in the chemical reaction. For example products produced from chemical industries Polymers and plastics, especially polyethylene, polypropylene, polyvinyl chloride, polyethylene terephthalate, polystyrene and polycarbonate are mostly chemical products. The resulting chemistry is used in a wide range of household goods, agriculture, construction, and service industries
Hapus