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3 years ago

Select ALL TRUE statements about enzyme cofactors / coenzymes.

Chemistry

1 answer:

olchik [2.2K]3 years ago

3 0

Answer: 1. True 2. False 3. True 4. False

Explanation:

1. True NAD+ is a co-enzyme synthesized from Niacin or Nicotinamide, a member of vitamin B complex. NAD+ is an important cofactor in cellular respiration. In the enzyme catalyzed reaction of Glyceraldehyde-3-P dehydrogenase and lactate dehydrogenase, NAD+ is an important cofactor.

2. False. Cofactor and co-enzymes are not irreversible changed. They are reversible. For example in the 5th step of glycolysis, two molecules of NAD+ are reduced to NADH. The conversion of pyruvate to lactate reconvert NADH to NAD+

3. True . Fe, Zn and Mg are enzyme cofactors. Zinc is a cofactor of alcohol dehydrogenase, carboxyl peptidase. Iron is a cofactor of cytochrome oxidase. Magnesium is a cofactor of Hexokinase.

4. False. Cofactors are optimal, and are not optional. Organisms can not function normally without cofactors.

For example when NAD+ is reduced to NADH in glycolysis the availability of NAD+ in the cell is limited. Therefore the absence of a cofactor becomes a bottleneck in the whole reaction process.

You might be interested in

How much hbro must be added to 1l of pure water to make a solution with a ph of 4.25? ka = 2.00 × 10−9 ?

RUDIKE [14]

Answer is: 153.52 grams of hypobromous acid <span>must be added.
</span>Chemical dissociation: HBrO ⇄ H⁺ + BrO⁻.
pH = 4.25.
pH = -log[H⁺].
[H⁺] = 10∧(-pH).
[H⁺] = 10∧(-4.25).
[H⁺] = [BrO⁻] = 5.62·10⁻⁵ M.
Ka = [H⁺] · [BrO⁻] / [HBrO].
2.00·10⁻⁹ = (5.62·10⁻⁵ M)² / [HBrO].
[HBrO] = 3.16·10⁻⁹ M² / 2.00·10⁻⁹.
[HBrO] = 1.58 M.
m(HBrO) = n(HBrO) · M(HBrO).
m(HBrO) = 1.58 mol · 96.91 g/mol.
m(HBrO) = 153.52 g.

3 0

4 years ago

Decane (C10H22) is used in diesel. The combustion for decane follows the equation: 2 C10H22 + 31 O2 à 20 CO2 + 22 H2O. Calculate

creativ13 [48]

The mass of water produced is 792 grams by the combustion of 568 grams of decane.

Given:

Combustion of 568 grams of decane with 2979 grams of oxygen.

$2 C_{10}H_{22 }+ 31 O_2 \rightarrow 20 CO_2 + 22 H_2O$

To find:

The mass of water produced by combustion of 568 grams of decane.

Solution:

Mass of decane = 568 g

Moles of decane :

= $\frac{568 g}{142 g/mol}=4 mol$

Mass of oxygen gas = 2976 g

Moles of oxygen gas:

= $\frac{2976 g}{32 g/mol}=93 mol$

$2 C_{10}H_{22 }+ 31 O_2 \rightarrow 20 CO_2 + 22 H_2O$

According to reaction, 2 moles of decane reacts with 31 moles of oxygen, then 4 moles of decane will react with:

$=\frac{31}{2}\times 4mol=62\text{ mol of}O_2$

But according to the question, we have 93.0 moles of oxygen gas which is more than 62 moles of oxygen gas.

So, this means that oxygen gas is present in an excessive amount. Which simply means:

Oxygen gas is an excessive reagent.
Decane is a limiting reagent.
Decane being limiting reagent will be responsible for the amount of water produced after the reaction.

According to reaction, 22 moles of water is produced from 2 moles of decane, then 4 moles of decane will produce:

$=\frac{22}{2}\times 4mol=44\text{mol of }H_2O$

Mass of 44 moles of water ;

$=44mol\times 18g/mol=792g$

792 grams of water is produced by the combustion of 568 grams of decane.

Learn more about limiting reagent and excessive reagent here:

brainly.com/question/14225536?referrer=searchResults

brainly.com/question/7144022?referrer=searchResults

3 0

3 years ago

Consider the balanced equation below.

wolverine [178]

Answer:

a) H2S:SO2 = 2:2 and O2:H2O = 3:2

Explanation:

2H2S + 3O2 → 2SO2 + 2H2O

⇒ H2S:SO2 = 2 mol H2S / 2 mol SO2 ≡ 2 : 2

⇒ O2:H2O = 3 mol O2 / 2 mol H2O ≡ 3 : 2

8 0

3 years ago

Consider the following set of ions: Al3+; Li+, Rb+, [(C4H9)4N+].

krok68 [10]

Hey there!:

a) Cations which are lowest size generally forms adopts more number of water molecules around it. Such kind of Cations forms largest hydrated ions. Among given cations, Li+ is smallest one and (C4H9)4N+ is largest one. So, Li+ ion forms largest hydrated ion.

b) Organic ligands or alkyl chains contained Cations are hydrophobic in nature due to its low polar nature. Among given (C₄H₉)4N⁺ cation is hydrophobic in nature.

c) Size of cation inversely proportional to the hydrated sphere or number of water molecules attached. So, in the given Cations (C₄H₉)4N⁺ is largest cation which attaches fewest water molecules.

d) Charge on the cation makes it more electrostatic maker. But size is inversily proportional to electrostatic property. (C₄H₉)4N⁺ is electrostatic structure breaker.

e) Al⁺³ has highest charge. So it is most electrostatic structure maker.

Hope this helps!

3 0

3 years ago

4. Think of the solids and liquids that you encounter every day. In what ways are solids and liquids similar? In what ways are t

Taya2010 [7]

Answer:

They both are the same thing which is water but they are just in different forms.

Explanation:

A solid is water that is frozen and a liquid is just water.

3 0

2 years ago