Answer:
1.874 M.
Explanation:
Molarity is defined as the no. of moles of a solute per 1.0 L of the solution.
M = (no. of moles of solute)/(V of the solution (L)).
∴ M = (mass/molar mass)of NiCl₂/(V of the solution (L)).
∴ M = (mass/molar mass)of NiCl₂/(V of the solution (L)) = (85.0 g / 129.59 g/mol)/(0.35 L) = 1.874 M.
Why do northern lights appear in different colors? Because charged particles of solar wind ignite different gases in Earth's atmosphere Because electrons and protons of solar wind ignite the plasma present in the corona Because electrons and protons of solar wind cause severe proton showers on Earth Because charged particles of solar wind cause solar flares on the surface of the sun
Answer:
It is A. Because charged particles of solar wind ignite different gases in Earth's atmosphere.
Explanation:
Since the solar wind from the sun is too radioactive for humans (they would die), once the charged particles hit the earth's atmosphere it shows its color. Every element has its own color and once it hits the atmosphere it really starts to show.
Because charged particles of solar wind ignite different gases in Earth's atmosphere is the correct statement.
The northern lights, also known as the auroras, are a natural phenomenon that occurs when charged particles from the Sun's solar wind interact with the Earth's magnetosphere and atmosphere. The solar wind consists of charged particles, mainly electrons and protons, that are ejected from the Sun's outer atmosphere.
As these charged particles enter the Earth's magnetosphere, they follow the planet's magnetic field lines and are funneled toward the polar regions. When they reach the Earth's atmosphere, they collide with atoms and molecules, particularly those of oxygen and nitrogen.
These collisions excite the atoms and molecules, causing them to release energy in the form of light. The specific colors observed in the auroras depend on the type of gas present in the atmosphere and the altitude at which the collisions occur. Oxygen atoms emit green and red light, while nitrogen atoms produce blue and purple light.
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What’s metamorphism
Explanation:
Hi!
Let's solve this!
Metamorphism is a process that involves rocks. This process occurs when they are subjected to a lot of pressure or temperatures.
This process also happens in the presence of fluids. There are different types of metamorphism such as dynamic, hydrothermal, shock, and others.
A sample of pure water is neutral because it contains
Answer:
A sample of pure water is neutral because it contains the same number of H₃O⁺ ions as OH⁻ ionsExplanation:
Neutral pH is 7.By definition pH = - log [H₃O⁺]Water ionizes according to this equilibrium equation:2 H₂O (l) ⇄ H₃O⁺ + OH⁺
So, the ionization (equlibrium) constant is:Kw = [H₃O⁺ ] [ OH⁺]
At 25°C, Kw = 1 × 10⁻¹⁴Hence: [H₃O⁺ ] [ OH⁺] = [H₃O⁺ ] ² = 1 × 10⁻¹⁴ ⇒ [H₃O⁺ ] = 10⁻⁷⇒ pH = - log (10⁻⁷) = 7If phosphorus (P) has 4 naturally occurring isotopes, phosphorus-29(32.7.%), phosphorus-30(48.03%), phosphorus-31(18.4%), and phosphorus-33 (0.87%), what is its average r.a.m.?
A. 29.9
B. 123
C. 100
D. 30.75
Answer:
A. 29.9
Explanation:
An element can have differing numbers of neutrons in its nucleus, but it always has the same number of protons. The versions of an element with different neutrons have different masses and are called isotopes. The average atomic mass for an element is calculated by summing the masses of the element’s isotopes, each multiplied by its natural abundance on Earth.Average atomic mass of P = ∑(Isotope mass)(its abundance)
∴ Average atomic mass of P = (P-29 mass)(its abundance) + (P-30 mass)(its abundance) + (P-31 mass)(its abundance) + (P-33 mass)(its abundance)
Abundance of isotope = % of the isotope / 100.
∴ Average atomic mass of P = (29)(0.327) + (30)(0.4803) + (31)(0.184) + (33)(0.0087) = 29.88 a.m.u ≅ 29.9 a.m.u.
So, the right choice is: A. 29.9
Isotopes of the same element will have a different number of neutrons, but the same number of protons. TRUE OR FALSE
Answer:
TRUE
Explanation:
A catalyst can speed up the rate of a given chemical reaction by
Decreasing the activation energy needed for the reaction.
Liquids that dissolve freely in one another in any proportion
Miscible-liquids that dissolve freely in one another in any proportion
Miscible liquids, such as ethanol and water, can be mixed together in any proportion to form solutions. Miscibility is a unique property that facilitates the infinite mutual solubility of these liquids. This concept is different from solubility, which pertains to a solid's ability to dissolve in a liquid, and Henry's law, that relates to gaseous solutes.
Explanation:The question pertains to liquids that can be mixed together in any proportions to form solutions. These liquids are referred to as miscible. Examples of such liquids include ethanol, sulfuric acid, and ethylene glycol, which are all miscible with water. Miscible liquids have infinite mutual solubility, meaning they can dissolve into each other in any ratio.
Miscibility is different from solubility, which refers to a solid's ability to dissolve in a liquid. In contrast, miscibility refers to the ability of two liquids to mix without separating into two stages. For instance, water and oil are considered immiscible because they cannot mix together and will instead separate into two layers.
Another important concept related to the behavior of solutions is Henry's law, which states that the concentration of a gaseous solute in a solution is proportional to the partial pressure of the gas to which the solution is exposed. This law, however, is more relevant when discussing solubilities for gaseous solutes.
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If the change of enthalpy of this reaction when proceeding left to right is +14 kcal, which chemical equation is correct?
N2O4 2 NO2 + 14 kcal
N2O4 + 14 kcal 2 NO2
Answer:
N₂O₄ + 14 kcal ⇄ 2NO₂.
Explanation:
Since the sign of ΔH determines either the reaction is exothermic or endothermic:
+ve, the reaction is endothermic.
-ve, the reaction is exothermic.
∵ The change of enthalpy of this reaction when proceeding left to right is + 14 kcal (+ ve sign).
∴ The reaction is endothermic, the heat is a part of the reacatnts in the reaction.
So, the reaction is:
N₂O₄ + 14 kcal ⇄ 2NO₂.
What would the molecule C₂H₄ be classified as?
Alkane
Inorganic compound
Alkyne
Alkene
Answer:
Alkene.
Explanation:
C₂H₄ is the formula of ethene.
C forms four bonds.
Its structure is: CH₂=CH₂.
The bond between the two carbon atoms is double bond.
When the hydrocarbon contains a double bond, it is classified as an alkene.
This is a mixture that has different properties throughout.
Answer:
Heterogenous mixture is a mixture that has different properties throughout.
Explanation:
Mixture refers to substances that are not chemically mixed together, that is, they can easily be separated by physical methods. There are two major types of mixture; these are heterogeneous and homogeneous mixtures. Homogeneous mixtures refer to those mixtures that are uniform in composition. A good example of this is tap water. Heterogeneous mixture on the other hand refers to those mixtures, which are not uniform in composition. A good example of this is a mixture of water and sand.
why is boron and beryllium an exception to the octet rule
Answer:
Explanation:
Beryllium especially, but Boron as well both exhibit metallic characteristics.
The outside ring of Beryllium contains 2 electrons. It would have to take on 6 electrons to have a ring of 8. The same statement can be made about Boron (except that it would need 5 electrons to make 8). It is easier for the atom to give up 2 or 3 than than to take on 5 or 6. It would not be easy to have a 5 or 6 minus charge on it.
Boron and beryllium are exceptions to the octet rule because they have less than eight electrons in their valence shell in some compounds, such as BF₃ and BeH₂, due to their position in Group III and the unique properties of their electrons.
Boron and beryllium are exceptions to the octet rule because they do not always complete an octet of electrons in their compounds. Boron, found in compounds like BF₃, tends to form compounds with only six valence electrons around the boron atom, rather than the eight suggested by the octet rule. Beryllium, on the other hand, often ends up with only four valence electrons as seen in the molecule BeH₂. These deviations from the octet rule occur because of the elements' positions in Group III of the periodic table, where elements commonly have fewer valence electrons than required to fulfill the octet. Thus, compounds of these elements are less predictable from the octet rule, which was primarily based on observations of the elements in Groups IV through VIII.
Incomplete octets are found in some compounds involving boron, aluminum, and beryllium, such as boron hydrides. The behavior of these elements is based on their tendency to form stable structures with fewer than eight electrons; boron atoms, for example, might follow a 'sextet rule' in some compounds but can achieve full octets in others like in its complex with ammonia, NH₃BF₃. Likewise, beryllium typically forms molecular compounds wherein it forms single covalent bonds without reaching an octet, due to its limited number of valence electrons and its small atomic size.
Which of the following is a single replacement reaction ?
Answer:
well its D Mg + 2HCl ----- MgCl2 + H2
Explanation:
Because Magnesium Replaces Hydrogen
Which of the following pairs of elements is most likely to form an ionic compound?1.Nitrogen and sulfur? OR 2. Magnesium and Fluorine?
Answer:
Magnesium and fluorine.Explanation:
Ionic compounds are formed by the electrostatic attraction of cations and anions.
Cations, positive ions, are formed when atoms lose electrons, and anions, negative ions, are formed when atoms gain electrons.
When two different atoms have similar atraction for electrons (electronegativity) they will not donate to nor catch electrons from each other, so cations and anions will not be formed. Instead, the atoms would prefer to share electrons forming covalent bonds to complete their outermost shell (octet rule).
Then, in order to form ionic compounds the electronegativities have to substantially different. This situation does not happen between two nonmetal elements, which nitrogen and sulfur are. Then, you can predict safely that nitrogen and sulfur will not form an ionic compound.
Ionic compounds, then require the electronegativity difference that exist between some metals and nonmetals. Being magnesium an alkaline earth metal, its electronegativity is very low. On the other hand, fluorine the first element of the group 17, has the highest electronegativity of all the elements.Thus magnesium and fluorine will have enough electronegativity difference to justify the exchange of electrons, forming ions and, consequently, ionic compounds.
Magnesium and Fluorine are the elements most likely to form an ionic compound.
Explanation:The pair of elements most likely to form an ionic compound is Magnesium and Fluorine.
Binary ionic compounds are composed of a metal (cation) and a nonmetal (anion). Magnesium is a metal and has a low ionization potential, meaning it easily loses electrons. Fluorine is a nonmetal and has a high electron affinity, meaning it readily gains electrons. These properties make it highly likely for magnesium and fluorine to form an ionic compound, such as magnesium fluoride (MgF2).
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What is the definition of work?
Answer:
activity involving mental or physical effort done in order to achieve a purpose or result.
Explanation:
The scientific definition of work is: using a force to move an object a distance .
A sample of lemon juice is found to have a pH of 2.3. What is the concentration of hydrogen ions in the lemon juice?
Answer: It's equal to 10^(-2.3), or 0.00501 M, or 5.01 * 10^-3 moles/Liter
Explanation:
Well, pH = - log[H+]
Or, in words, pH is equal to -1 multiplied by the logarithm (base 10) of the hydrogen ion concentration. So you have 2.3 = -log[H+]. We want to isolate the H+, so let's start simplifying the right hand side of the equation. First, we multiply both sides by -1. -2.3=log[H+] Now, the definition of a logarithm says that if the log (base 10) of [H+] is -2.3, then 10 raised to the -2.3 power is [H+] So on each side of the equation, we raise 10 to the power of that side of the equation. 10^(-2.3) = 10^(log[H+]) and because 10^log cancels out... 10^(-2.3) = [H+] Now we've solved for [H+], the hydrogen ion concentration!
A sample of lemon juice is found to have a pH of 2.3. 5.012×10−3 moles per liter is the concentration of hydrogen ions in the lemon juice.
What is pH ?The pH scale, which previously stood for "potential of hydrogen," is used to describe how acidic or basic an aqueous solution is. The pH values of acidic solutions are typically lower than those of basic or alkaline solutions.
The pH scale determines how acidic or basic water is. The range is 0 to 14, with 7 representing neutrality. A base is present when the pH is higher than 7. In reality, pH is a measurement of the proportion of free hydrogen and hydroxyl ions in water.
Lemon juice is 10,000–100,000 times more acidic than water, with a pH between 2 and 3. (1, 2, 3). The pH of food is a gauge of how acidic it is. Lemon juice is acidic because its pH ranges from 2 to 3.
pH = -log [ H+ ]
2.3 = -log [ H+ ]
-2.3 = log [ H+ ]
10^( -2.3 ) = 10^( log [ H+ ] )
10^(-2.3) = [ H+ ]
[ H+ ] = 5.012×10−3 moles per liter.
Thus, A sample of lemon juice is found to have a pH of 2.3. 5.012×10−3 moles per liter is the concentration of hydrogen ions in the lemon juice.
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An acid is any substance that
A: increases a solution's pH
B: produces hydroxide ions
C: donates a proton
D: acts as a hydrogen acceptor
Answer:
C
Explanation: a is incorrect since the lower the ph = more acidic and b is incorrect because it produces hydronium ion and d I’m not sure what it is but I no that base recieve the protons
All of the following equations are statements of the ideal gas law except
a. P = nRTV
b. PV/T = nR
c. P/n = RT/v
d. R = PV/nT
Answer:
The first equation, a. PV = nRT, is not a valid statement of the ideal gas law.Explanation:
The basic expression for the ideal gas law is:
[tex]pV=nRT[/tex] .......... [Equation 1]Where:
n is the number of moles of the gasV is the volume occupied by the gasp is the pressure exerted by the gas moleculesT is the temperature in absolute scale (Kelvin)R is the Universal gas constant (0.0821 atm-liter /K-mol or the equivalents in other units)You can perform different algebraic operations to obtain equivalent equations:
Choice b) Divide equation 1 by T and you get:
pV / T = nR, which is the choice b. from your list.Choice c) Divide equation 1 by n × V and you get:
p/n = RT / V, which is the choice c. from your list.Choice d) Divide equation 1 n × T and you get:
pV / (nT) = R, which is the choice d. from your list.The choice a. p = nRTV states that p and V are in direct relation, when the ideal gas law states that p and V are inversely related, so that equation is wrong.
Conclusion: the choice a, p = nRTV, is not a statement of the ideal gas law.
The option that does not represent the ideal gas law is a. P = nRTV. The correct form of the ideal gas law is PV = nRT, and options b, c, and d can be rearranged to match this form.
The correct form of the ideal gas law is PV = nRT. Let's break down each option:
a. P = nRTV: This is incorrect because it does not correctly isolate P and mismatches the variables.b. PV/T = nR: Rearranging this gives PV = nRT, which is correct.c. P/n = RT/v: This can be rearranged to P = (nRT)/V, which is also correct.d. R = PV/nT: Rearranging gives PV = nRT, which is correct.Thus, the statement that does not represent the ideal gas law is a. P = nRTV.
Page 705 #12/#13: Use the changes in oxidation numbers to identify which atom is oxidized, reduced, the oxidizing agent, and the reducing agent. 5
A.
2H2(g) + O2(g) → 2H2O(l)
B.
2KNO3(s) → 2KNO2(s) + O2(g)
Concepts to understand before solving:
-Oxygen is ALWAYS reduced
-OIL- Oxidation Is Loss of electrons
-RIG- Reduction Is Gain of electrons
-the element that is oxidized is the reducing agent
-the element that is reduced is the oxidizing agent
A. 2H2 + O2 —> 2H2O
O is reduced, making it the oxidizing agent
H is oxidized, making it the reducing agent
B. 2KNO3 —> 2KNO2 + O2
O is reduced, making it the oxidizing agent
KNO is oxidized, making it the reducing agent
Which of the following is the trend down a period?
A. The number of complete electron shells increases by one.
B. The number of complete electron shells stays the same.
C. The number of outer shell electrons decreases by one.
D. None of these.
Answer:
B. The number of complete electron shells stays the same.
Explanation:
The periods on a periodic table consists of those elements that are arranged in the horizontal row in the periodic table.
Elements in the same period have the same number of electron shells and this corresponds to the period. This implies that elements of period 2 have two electron shells, those of period 3 have three shells and so on.
The number of Valence electrons of the elements on the same period increases progressively by one across the period from left to right.
A group is the vertical column to which elements are arranged on the periodic table. Elements in the same group have the same number of Valence electrons and the number of shell increases down a group.
When we go down a period, the number of shell stays the same.
Which of the following statements describes alkenes and alkynes but not alkanes?
A. They are aromatic compounds.
B. They are unsaturated.
C. They are saturated.
D. They are hydrocarbons.
Answer:
B. they are unsaturated
Explanation:
Alkanes are long chain hydrocarbons with only single bonds, alkenes are hydrocarbons with at least one double bond and alkynes are hydrocarbons with at least one triple bond.
Alkanes, alkenes and alkynes are all hydrocarbons. Therefore statement D. is incorrect
Hydrocarbons are compounds containing carbon and hydrogen only
Neither of the three are aromatic compounds therefore statement A is incorrect
Saturated hydrocarbons are where all the bonds between atoms are single bonds. Unsaturated hydrocarbonds are when at least there's one double or triple bond.
Alkanes are saturated and Alkynes and alkenes are unsaturated.
therefore statement B is correct where alkenes and alkynes are unsaturated but alkanes are not
Final answer:
Alkenes and alkynes are unsaturated hydrocarbons due to the presence of carbon-carbon double and triple bonds, respectively, differentiating them from saturated alkanes.
Explanation:
The correct answer to the question is B: Alkenes and alkynes are unsaturated hydrocarbons. This is because they contain double or triple carbon-carbon bonds respectively, which means they have fewer hydrogen atoms attached to the carbon backbone compared to alkanes, which contain only single bonds and are therefore saturated. The term saturated indicates that a molecule contains the maximum possible number of hydrogen atoms whereas unsaturated indicates the presence of double or triple bonds, which replace some hydrogen atoms.
Aromatic compounds, like benzene, are indeed hydrocarbons but they are classified by their distinct ring structure with delocalized electrons, which is not a characteristic of alkenes or alkynes. Alkenes and alkynes are not aromatic simply because they have unsaturated bonds. Alkanes are also hydrocarbons; however, they are saturated, which is a term not applicable to alkenes or alkynes.
The requirement that a reversible reaction be at equilibrium is that:
- the concentrations on the two sides of the arrow be equal
- the velocity for the forward reaction equal that of the reverse reaction
- there will be as many molecules of the substances on one side of the arrow as there are molecules of the substances on the other side
- the moles of products will equal the moles of reactants
The velocity for the forward reaction equal that of the reverse reaction.
Answer: - the velocity for the forward reaction equal that of the reverse reaction
Explanation:-
Equilibrium constant is defined as the ratio of concentration of product to the concentration of reactants each raised to the power their stoichiometric ratios. It is represented by the symbol 'K'. For the general equilibrium equation:
[tex]aA+bB\rightleftharpoons cC+dD[/tex]
The expression for equilibrium constant is given as:
[tex]K=\frac{[C]^c[D]^d}{[A]^a[B]^b}[/tex]
Characteristics of equilibrium reaction:
Chemical equilibrium are attained is closed system.
The macroscopic remains constant like: volume, pressure, energy etc.
Rate of forward reaction is equal to the rate of backward reaction. The concentration of the reactants and products remain constant.They are not always equal.
What scientist has a element named for them?
Niel bohr - Bohrium 107
What element is named after a country in the Western Hemisphere?
Americium is an element named for a country in the Western Hemisphere
The element named after a location in the Western Hemisphere is Tennessine (Ts), named after Tennessee. Naming elements after locations or scientists is customary in chemistry, pending approval by IUPAC.
Explanation:The element named after a country in the Western Hemisphere is Tennessine, with the symbol Ts. Element 117, Tennessine, was proposed by a team of scientists from Russia and the United States, named after the state of Tennessee. Naming elements after locations, particularly cities, regions, or countries is one of the traditions followed in the scientific community, as seen when a Russian research team named element 118 Oganesson, symbol Og, after the scientist Yuri Oganessian, who made significant contributions to the discovery of heavy elements.
Traditionally, it is typical for the discoverers of a new element to propose a name, which is then subject to approval by the International Union of Pure and Applied Chemistry (IUPAC) before it becomes official. Before getting their final names, elements may carry temporary systematic names based on Latin numbers corresponding to their atomic numbers.
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What is the first quantum number of a 1s2 electron in phosphorus, 1s22s22p63s23p3?
Answer: Im pretty sure n=1 as thats the first one indicated.
Explanation:
Answer:
n=1
Explanation:
In a(n) _____ reaction, the products are at a higher energy level than are the reactants.
Select one:
a. endothermic
b. activation
c. exothermic
d. catalytic
Answer:
In an endothermic reaction, the products are at a higher energy level than are the reactants.
Explanation:
Endothermic reaction has positive ΔH.ΔH = E products - E reactants.
So, for endothermic reactions, the products are at a higher energy level than are the reactants.
Kindly see the attached image.
So, the right choice is: a. endothermic.Which of the following would increase the rate of a chemical reaction between hydrochloric acid (HCl) and solid zinc metal (Zn)? A. Decreasing the amount of Zn B. Performing the reaction at a lower temperature C. Pulverizing the zinc metal into a fine powder D. Decreasing the concentration of HCl
Answer:
C. Pulverizing the zinc metal into a fine powder
Explanation:
Pulverizing the zinc metal into a fine powder would increase the rate of chemical reaction between hydrochloric acid and zinc metal.This can be explained by the fact that pulverizing the zinc metal into fine powder will increase the surface area or the area of contact with the other reactant, HCl, thus making the reaction rate increase.Increase in surface area of the reactant Zinc increases the frequency of collision between the reactant particles, and in turn increasing the rate of reaction.Answer: C. Pulverizing the zinc metal into a fine powder
Explanation:
is immoral an adaptation?
Answer:
Immoral means not moral and connotes evil or licentious behavior. Amoral, nonmoral, and unmoral, virtually synonymous although the first is by far the most common form, mean utterly lacking in morals (either good or bad), neither moral nor immoral.
so I would say no
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what are polymers?
a.)small groups of carbon molecules
b.) long chains of halogen molecules
c.)long chain of carbon molecules
d.) small groups of halogen molecules
Answer:
c.)long chain of carbon molecules
Explanation:
A polymer is a long chain of many monomers joined together using chemical bonds.For example, a long chain of carbon molecules may form a polymes such as fatty acid.An example of polymers are proteins whose monomers are amino acids, cellulose and glycogen whose monomers are monosaccharides.Double jeopardy clauses in the fifth amendment make it impossible for a person to be tried of the same crime he’d been exonerated from in the past. Why do you think this is important ?
Answer:
This definitely is important:
Explanation:
Because if the police, FBI, etc., find something else about the case where the man has already been tried for the entire case, otherwise known as the same crime, and not convicted, there is literally nothing that any of them can do because the government would be looked at as not working fast enough. BUT it is also important simply because of the fact that if you are someone who has been tried for the crime, and you weren't actually the one who did it or even simply witnessed it, they can't try you for that same crime even if they find a small smidge as to how you are involved, or if you even witnessed or HEARD it happening. Police sometimes try to convict the person who heard the crime happening simply because they don't know what else to do, or even to try to get the case closed to work on something else, because if you heard the crime happening, then it's counted as involvement in the investigation and the police could also think that it means that you're also involved in the crime itself, but don't have any other evidence as to why or how you could be the criminal in the investigation. It does happen, even if certain or lots of simply random people admit or not.
The double jeopardy clause in the Fifth Amendment is important for several reasons.
Why is this important?The double jeopardy clause in the Fifth Amendment is significant for a few reasons.
First, it stops the government from bothering and punishing people. If the government could try someone again for a crime they were already found not guilty of, it could use its power to overpower the defendant and make it hard for them to have a fair trial.
The double jeopardy clause keeps people from having to go through the emotional and psychological pain of being tried for the same crime more than once. Going through a trial can be very stressful, and being put on trial more than once for the same crime can be really tough.
The double jeopardy clause helps make sure that once someone has been tried and convicted for a crime, they can't be tried and convicted again for the same crime. When someone is found not guilty of a crime, they should be allowed to continue with their life without worrying about facing another trial.
In simple words, the double jeopardy clause helps protect people's rights and keeps the criminal justice system fair. It makes sure that people are not bothered or harmed by the government, and that they don't have to go through the emotional and mental stress of facing many trials for the same crime.
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Which of the following molecules would you expect to act as allosteric activator of an enzyme in glycolysis?ADPNADP+pyruvateNADPH
in absence of oxygen.
i have resd about in my biology textbook.
sorry i kniw this much