Answer:
Because of statements (a), (c) and (d).
Explanation:
Let's evaluate each statement to know why they focus on higher alcohols instead of ethanol:
(a) It is easier to produce higher alcohols in microbes than it is to produce ethanol<u>.</u> This is true<u> since ethanol is the major biofuel in the world because it can be easily produced by fermentation technology developed a long time ago. Recently, higher alcohols are produced from microorganisms that are used as microbial cell factories.</u>
(b) Higher alcohols have a higher hygroscopicity than ethanol. This is false since ethanol is more hygroscopic than higher alcohols.
(c) Higher alcohols have a lower vapor pressure than ethanol. This is true, ethanol has a higher vapor pressure than higher alcohols. The vapor pressure is important since it can affect the proper cold starting of the engine.
(d) Higher alcohols have a higher energy density than ethanol. This is true since the production of higher alcohols as biofuels is more desirable than the ethanol because higher alcohols have a high energy density and other more advantages than the use of ethanol.
Therefore the answer of why did they focus on higher alcohols to add to or substitute gasoline instead of ethanol is because of the statements (a), (c) and (d).
I hope it helps you!
The coefficients : 3, 2, 1,3
<h3>Further explanation</h3>
Given
Reaction
Mg + H3PO4 -> Mg3(PO4)2 + H2
Required
The coefficients
Solution
Steps to balance reactions:
1. Give a coefficient(The most complex compound is assigned a coefficient of 1)
aMg + bH₃PO₄ ⇒ Mg₃(PO₄)₂ + cH₂
2. Make an equation
Mg, left = a, right = 3 ⇒a=3
P, left = b, right = 2⇒b=2
H, left = 3b, right = 2c⇒3b=2c⇒3.2=2c⇒2c=6⇒c=3
The equation becomes :
<em>3Mg + 2H₃PO₄ ⇒ Mg₃(PO₄)₂ + 3H₂</em>
Answer:
0.492 lb/in^3
Explanation:
From Density of Mercury (13.6g/cm3) given,
Mass = 13.6g
Volume = 1cm3
Now we covert these variables as follows :
For Mass:
454 g = 1 lb
13.6g = 13.6/454 = 0.03lb
For volume:
2.54 cm = 1 in
1cm = 1/2.54 = 0.394in
Volume = (0.394in)^3 = 0.061 in^3
Density = Mass /volume
Density = 0.03lb/0.061 in^3
Density = 0.492 lb/in^3
Answer:
because its not international language
Explanation:
because its not international language like English
Answer:
Alpha helixes:
- form long thin structures important for transmembrane proteins
- have a rigid spring like structure around a central axis
Beta sheets:
- Keep their shape due to hydrogen bonds between adjacent polypeptides chains
- have a flat zig zag like structure
Explanation:
Alpha helices and beta pleated sheets are two types of secondary structure found in proteins.
Alpha helix: In this structure, the polypeptide backbone is tightly wound around an imaginary central axis drawn longitudinally through the center with the R groups of the amino acids protruding outward from the helical backbone. This structure looks like a spring and could either be a left-handed or right-handed helix, though the left-handed helix has not been observed in proteins. Each turn of the helix includes about 3.6 amino acid residues.
The alpha helix is stabilized by a hydrogen bond between the hydrogen atom attached to the electronegative nitrogen atom of a peptide linkage and the electronegative carbonyl oxygen atom of the fourth amino acid on the amino-terminal side of that peptide bond.
Alpha-helices due to their structure, are the most common transmembrane proteins- protein structure element that crosses biological membranes.
Beta sheets: In the beta conformation, the backbone of the polypeptide chain is extended into a zigzag structure. The zigzag polypeptide chain can be arranged side by side to form a structure resembling a series of pleats known as beta sheets. Hydrogen bonds formed between adjacent segments of the polypeptide chain functions to stabilize the structure.
The beta comformation in the form of turns is common in globular proteins.