PLS HELP!!!

Match the terms to the appropriate definitions or descriptions

Answer:

To calculate the molarity of a calcium carbonate (CaCO3) solution, we first need to convert the volume of water from milliliters (mL) to liters (L).

Volume of water = 125 mL = 0.125 L

Next, we need to use the number of moles of CaCO3 and the volume of water to calculate the molarity:

Molarity = number of moles / volume of solution

Molarity = 2.00 mol / 0.125 L

Molarity = 16.0 M

Therefore, the molarity of the calcium carbonate solution is 16.0 M. However, it's important to note that this concentration is not physically possible as the solubility of calcium carbonate in water is relatively low. Therefore, it's likely that the amount of calcium carbonate that actually dissolves in 125 mL of water is much less than 2.00 moles, making the actual molarity much lower.

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62.297 kJ of heat is required  to boil 132.g of water (H20), beginning from a temperature of 7.4 °C.

The quantity of heat required to boil 132 g of water at a temperature of 7.4°C is to be calculated. The heat energy required to increase the temperature of a material by one degree Celsius is referred to as heat capacity or specific heat. The formula for specific heat capacity is given by Q = mCΔT where Q is the quantity of heat, m is the mass of the material, C is the specific heat capacity of the material, and ΔT is the difference in temperature.

We'll utilise the following formula to calculate the heat required:q = m x c x ΔT + m x Lwhere q is the quantity of heat, m is the mass of the material, c is the specific heat of the material, ΔT is the difference in temperature, and L is the material's latent heat of vaporization.

The value of q can now be calculated : q = (132.0 g) × (4.184 J/g°C) × (100°C – 7.4°C) + (132.0 g) × (2.26 × 106 J/kg)q = 62297.0 J. The heat required to boil 132 g of water beginning at 7.4°C is 62297.0 J. This means that 62.297 kJ of heat is required.

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The (b) claim is true. 3 covalent bonds are often formed by atoms having 3 valence electrons. A, c, and d are false statements.

Covalent bonds are created when atoms share electrons in order to finish the valence shell, the atom's outermost electron shell. In order to completely fill their valence shell, atoms having three valence electrons, like boron, often establish three covalent bonds. The boron atom can then achieve a stable configuration that is comparable to the noble gas configuration as a result. Nevertheless, contrary to what assertions a, c, and d indicate, atoms with 5, 7, or 8 valence electrons do not often form the same number of covalent bonds. In order to complete their valence shell, they often create fewer bonds by sharing electrons with other atoms.

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The  correct answer is d All of the above

The protonation of a neutral ketone creates an electrophilic species that is activated toward nucleophilic attack, which is said to occur under acid-catalyzed conditions.

Therefore, All of the above are true: the resulting species becomes more electrophilic, subsequent nucleophilic attack on the resulting species is said to occur under acid-catalyzed conditions, and the resulting species has a positive charge.

Wat is a ketone?A ketone is an organic compound with a carbonyl group (CO) bound to two other carbon atoms.

The chemical formula for a ketone is RCOR′, where R and R′ can be any group from the periodic table.

Ketones are classified as carbonyl compounds since they contain a functional group with a carbon atom double-bonded to an oxygen atom.

When the carbonyl group of a neutral ketone is protonated, the resulting species is activated toward nucleophilic attack.

When the  group of a neutral ketone is protonated, the carbonyl carbon atom acquires a partial positive charge, and the oxygen acquires a partial negative charge

As a result, the carbonyl carbon atom becomes more electrophilic than before. The carbonyl group of the resulting species is more prone to nucleophilic attack than it was in the original ketone. The nucleophile can be a negative ion or a lone pair of electrons.

Subsequent nucleophilic attack on the resulting species is said to occur under acid-catalyzed conditions.

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"Late-movers have a substantial advantage in this market since inventory should be cheaper to acquire for those firms that have entered markets more recently" is not true regarding the competitive dynamics. This is because late-movers face many challenges.

Sharing economy refers to a peer-to-peer (P2P) networking concept where consumers and organizations have the opportunity to share, sell, or rent products and services to one another directly without the involvement of middlemen. The sharing economy includes various industries, such as ride-sharing, accommodation-sharing, co-working spaces, and others.

The competitiveness of a sharing economy marketplace is influenced by factors such as the number of competitors, the level of brand recognition, pricing strategies, product quality, customer service, and others. When new entrants join a sharing economy market, existing players will have to adjust to remain competitive. Therefore, it is vital for market participants to monitor the competition's tactics and come up with new strategies to stay ahead of the curve.

However, late-movers do not have a substantial advantage in this market since inventory should be cheaper to acquire for those firms that have entered markets more recently is not true regarding the competitive dynamics of most sharing economy marketplaces.

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This balanced equation represents the principle of conservation of atoms, which is a fundamental principle of chemistry in the sense that the number and type of atoms are the same on both sides which means that no atoms were created or destroyed during the reaction, only rearranged to form new molecule.

A balanced equation is described as an equation for a chemical reaction in which the number of atoms for each element in the reaction and the total charge are the same for both the reactants and the products.

Analyzing the diagram,

1 nitrogen atom (N)

3 hydrogen atoms (H)

1 carbon atom (C)

2 oxygen atoms (O)

1 nitrogen atom (N)

4 hydrogen atoms (H)

1 carbon atom (C)

2 oxygen atoms (O)

This can only mean that no atoms were created or destroyed during the reaction, only rearranged to form new molecules.

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Answer:

The balanced equation for the decomposition of potassium chlorate is:

2KClO3 → 2KCl + 3O2

This equation tells us that for every 2 moles of KClO3 that decompose, 3 moles of O2 are produced.

To calculate the mass of KClO3 needed to produce a one-day supply of oxygen for an adult, we first need to calculate the amount of oxygen consumed per day by an average adult. We are given that the average adult consumes 909 g of O2 per day.

We can use the molar mass of O2 to convert grams to moles:

1 mol O2 = 32 g

909 g O2 = 28.4 mol O2

Next, we need to determine how much KClO3 is needed to produce 28.4 mol of O2. From the balanced equation, we know that 2 moles of KClO3 are needed to produce 3 moles of O2.

So, the number of moles of KClO3 needed is:

(28.4 mol O2) × (2 mol KClO3/3 mol O2) = 18.93 mol KClO3

Finally, we can use the molar mass of KClO3 to convert moles to grams:

1 mol KClO3 = 122.55 g

18.93 mol KClO3 = 2,322 g KClO3

Therefore, to provide a one-day supply of oxygen for an adult consuming 909 g of O2 per day, an oxygen candle would need approximately 2,322 grams of potassium chlorate.

The homo of the nucleophile in a reaction set for organic chemistry is the highest occupied molecular orbital (HOMO), which is the highest energy orbital that contains at least one electron.

The lowest unoccupied molecular orbital (LUMO) of the electrophile is the lowest energy orbital that does not contain any electrons.

When attempting a reaction set for organic chemistry, the HOMO of the nucleophile will react with the LUMO of the electrophile to form a new bond. The HOMO is considered to be the electron-rich species and the LUMO is considered to be the electron-poor species.

This interaction between the two species leads to the formation of the new bond. The nature of the new bond is determined by the nature of the two species.

If the two species are of the same element, the bond is covalent. If the two species are of different elements, the bond is polar covalent or ionic depending on the difference in electronegativity between the two species.

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The statement that best states how the author conveys her purpose for writing the article is: b. The author presents researchers who are utilising biometric technology in a number of ways.

Biometric technology is a type of technology that uses physical or behavioural characteristics unique to an individual to authenticate their identity. These characteristics can include fingerprints, facial features, voice patterns, iris or retinal patterns, hand geometry, and even behavioural traits such as typing rhythm and gait.

Throughout the article, the author discusses different examples of how biometric technology is being used in different fields, such as healthcare, law enforcement, and travel. The author is presenting these examples to showcase the potential and versatility of biometric technology and its benefits in various contexts. Therefore, option b best describes the author's purpose in writing the article.

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An exothermic chemical reaction between a solid and a liquid results in gaseous products. It is a spontaneous reaction.

When a chemical reaction takes place with the release of heat, it is known as an exothermic chemical reaction. An exothermic chemical reaction is a chemical reaction that releases energy in the form of heat, light, or sound during the process. The burning of paper is an example of an exothermic chemical reaction. When paper burns, heat and light are produced, which we can feel or observe.

The reaction is spontaneous if the Gibbs free energy, delta G is negative. A reaction will be spontaneous if its delta G is negative. The reaction will proceed from left to right if delta G is negative, and it will proceed from right to left if delta G is positive. A reaction will be at equilibrium if delta G is zero.The reaction mentioned in the question is an exothermic chemical reaction because it results in the release of heat. As a result, the reaction is spontaneous. The production of gaseous products indicates that a gas is formed during the reaction. Therefore, this reaction is spontaneous.

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Answer: Carbon's valence shell is unique because it has 4 valence shell electrons, which means it is less likely to gain or lose electrons to other elements. Rather, it shares its electrons. In other words, it tends to form covalent bonds (4) rather than ionizing. This results in carbon being able to form long chains or rings.

Answer:

a) Ethanol + K2Cr2O7 / H+ / Reflux → Acetaldehyde

CH3CH2OH + [O] → CH3CHO

b) Ethanol + K2Cr2O7 / H+ / Distil → Ethene

CH3CH2OH + [O] → CH2=CH2 + H2O

c) Propan-1-ol + K2Cr2O7 / H+ / Reflux → Propanal

CH3CH2CH2OH + [O] → CH3CH2CHO

d) Propan-2-ol + K2Cr2O7 / H+ / Reflux → Propanone (acetone)

(CH3)2CHOH + [O] → (CH3)2CO

e) 3-Methylbutan-1-ol + K2Cr2O7 / H+ / Reflux → 3-Methylbutanal

CH3CH(CH3)CH2CH2OH + [O] → CH3CH(CH3)CH2CHO

f) 4-Chloropentan-1-ol + K2Cr2O7 / H+ / Distil → 4-Chloropentanal

Cl(CH2)3CH2CH(OH)CH3 + [O] → Cl(CH2)3CH2CH=O + H2O

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Here are the given properties. The task is to decide whether each property is a physical property or a chemical property:

1. Solubility: Physical property

2. Flammability: Chemical property

3. Reactivity: Chemical property

4. Color: Physical property

5. Density: Physical property

6. Melting point: Physical property

There are two types of properties: Physical property and Chemical property. In this task, we have to identify which property among Solubility, Flammability, Reactivity, Color, Density, Melting point is Physical property or Chemical property.

A Physical property is a characteristic that defines the behavior or appearance of a substance without any changes in its composition. Physical properties can be identified by measuring, observing, or using physical methods.

A Chemical property is a characteristic that defines the behavior or the ability of a substance to undergo a chemical change or to transform into a new substance. The correct answer is given above.

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The given statement that "the rate of a second order reaction can depend on the concentrations of more than one reactant" is true because the rate of the reaction is proportional to the concentration of both reactants.

The second-order reaction is a chemical reaction in which two reactants interact and the rate of the reaction is proportional to the concentration of both reactants or to the square of the concentration of a single reactant. The equation is as follows:

k = k[reactant1] [reactant2] or k = k[reactant1]²

The reaction rate constant (k) for a second-order reaction is proportional to the concentration of one or two reactants. The concentration of the reactants has an impact on the reaction rate, as indicated by the order of the reaction.

Therefore, the statement that "the rate of a second order reaction can depend on the concentrations of more than one reactant" is true.

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The mass of Ca is 0.355 g.

Tums tablet has a mass of 0.565 g.

A 0.196 g piece of the tablet is found to contain 0.123 g of Ca.

Mass percent = (Mass of element in the compound / Mass of the compound) × 100

The mass of Ca in the given piece is,

The mass percent of Ca = (Mass of Ca in the given piece / Mass of the given piece) × 100

= (0.123 / 0.196) × 100 = 62.75510204 %

This means, in every 100 grams of Tums tablet, Ca is present in 62.75510204 grams (approximately).

Therefore, the mass of Ca in 0.565 g of Tums tablet is,

Mass of Ca in 0.565 g of Tums tablet = 0.565 × (62.75510204 / 100) = 0.3546475852 g ≈ 0.355 g

The mass (in grams) of Ca in the whole tablet is approximately 0.355 g.

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Answer:

The only difference is that ozone is made up of three oxygen atoms, while the stuff we breathe (molecular oxygen) is made up of only two atoms. Solar rays high in the atmosphere convert O2 to O3. In the upper atmosphere, rays from the Sun break a normal oxygen molecule into two separate oxygen atoms.

The distance between an electron and the nucleus for an electron in a certain orbit is set in the Bohr model of the atom. According to Bohr's hypothesis, electrons travel in circular orbits around the nucleus at set distances that represent various energy levels.

These orbits are also known as "energy levels" or "stationary states."

For an electron in a certain orbit, the distance between the electron and the nucleus is set in the Bohr model of the atom. In accordance with Bohr's hypothesis, electrons orbit the nucleus in a circle at regular intervals that correspond to various energy levels. Sometimes these orbits are referred to as "energy levels" or "stationary states." The electron's location is instead defined by a probability distribution known as an orbital in more recent quantum mechanical models of the atom, such as the Schrödinger equation. In contrast to the fixed orbits in the Bohr model, an orbital's size and shape can change depending on the energy of the electron and the arrangement of the atoms.

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In the pictured cell, the side containing zinc is the anode and the side containing copper is the cathode. The purpose of the Na2SO4 is to facilitate the transfer of electrons from the anode to the cathode.

A cell is a unit of life that is the smallest and most simple living organism, it can be classified as a complete organism, with all of the components that make up a living being, including DNA, membranes, and organelles. A voltaic cell is a device that converts chemical energy into electrical energy, it is also known as a galvanic cell or a Daniell cell. It is made up of two different metals that are submerged in an electrolyte solution that enables the transfer of electrons from one electrode to the other. The anode is the electrode that oxidizes and loses electrons during a redox reaction, this electrode is negatively charged, as it is the site of the oxidation reaction that releases electrons and generates an electrical current.

A cathode is an electrode that is reduced and gains electrons in a redox reaction, this electrode is positively charged and acts as a sink for electrons, absorbing them and using them to create a reduction reaction that generates an electrical current. The Na2SO4 in the pictured cell is an electrolyte solution that facilitates the transfer of electrons from the anode to the cathode. The salt dissociates into Na+ and SO42- ions, which then migrate toward the anode and cathode, respectively, where they can participate in redox reactions that generate an electrical current. This flow of ions helps to maintain a balance of charge in the cell and enables the transfer of electrons to occur more efficiently.

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The phenomenon in which electrons that are closer to the nucleus slightly repel those that are farther out is known as Shielding.

Electrons in an atom are negatively charged particles, and they are attracted to the positively charged nucleus. However, the outer electrons of an atom are also repelled by the inner electrons that are closer to the nucleus. This repulsion is due to the negative charges of the electrons, and it partially cancels out the attraction of the nucleus for the outer electrons.

Shielding is the phenomenon in which electrons that are closer to the nucleus slightly repel those that are farther out. This makes it possible for electrons in higher energy levels to be farther from the nucleus, so they are less strongly attracted and easier to remove.

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Answer: A food chain shows what eats what.  A food web is made up of all the food chains in the ecosystems.

Explanation: Hope that helps!

Answer:

Explanation:

A food chain outlines who eats whom.

A food web is all of the food chains in an ecosystem.

Le Chatelier's principle predicts that when a stress or change is added to a system at equilibrium, the system will adjust in order to counteract the stress or change. The principle can be used to describe the shift in the direction of the chemical equilibrium in response to changes in pressure, temperature, or concentration.

Le Chatelier's principle states that when the temperature is increased, the equilibrium system will absorb the heat by shifting the equilibrium position in the direction that uses up the heat energy. If heat is a product of the reaction, the equilibrium will shift to the left. If heat is a reactant, the equilibrium will shift to the right.

Here, in the case of the reaction of nitrogen and hydrogen to create ammonia:

N₂(g) + 3H₂(g) ⇌ 2NH₃(g), ∆H = −92 kJ/mol

The reaction produces heat, therefore the reaction is exothermic. An increase in temperature will cause a shift in equilibrium to the left, as the reaction will try to use up the excess heat. This means that the reaction will reduce the amount of NH₃ in the system, leading to a decrease in the concentration of NH₃.

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The correct match are: q = nCAT for Heating or cooling within a phase if moles are given, q = NAΔH for Heating or cooling during a phase change, and q = mcΔT for Heating or cooling within a phase if mass is given.

q = nCAT is used to calculate Heat lost or gained when heating or cooling within a phase if moles are given. In this equation, n is the number of moles, C is the heat capacity of the substance, A is the temperature change.

q = NAΔH is used to calculate Heat lost or gained when heating or cooling during a phase change. In this equation, N is the number of moles, ΔH is the enthalpy of fusion or vaporization.

q = mcΔT is used to calculate Heat lost or gained when heating or cooling within a phase if mass is given. In this equation, m is the mass of the substance, c is the specific heat capacity of the substance, ΔT is the temperature change.

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Molecules of the following substances are: (A) Cytochrome, (B) FADH2, (C) NAD+, (D) NADP+, (E) Oxygen (O2).

NAD+ is an intermediate electron acceptor for oxidations that occur in both glycolysis and in Krebs cycle reactions among the given substances.

Cytochrome: It is a heme-containing enzyme, which is responsible for the transfer of electrons during respiration.

It is found in the respiratory chain of the mitochondria, which is also called the electron transport chain. This chain is responsible for generating ATP during oxidative phosphorylation.

FADH2: Flavin adenine dinucleotide, also known as FAD, is a coenzyme involved in energy metabolism.

It is produced as a byproduct of the Krebs cycle and transfers electrons to the electron transport chain to create a proton gradient used to produce ATP. It is a redox-active molecule.

NAD+: Nicotinamide adenine dinucleotide, also known as NAD or NADH, is a coenzyme involved in energy metabolism.

NAD+ is the oxidized form of NADH, and the conversion of NAD+ to NADH is a key step in the Krebs cycle.

It accepts electrons from other molecules and becomes reduced, and then it transfers those electrons to other molecules in the cell.

NADP+: Nicotinamide adenine dinucleotide phosphate, also known as NADP or NADPH, is a coenzyme that acts as an electron carrier in metabolic processes.

It is important in anabolic reactions, such as lipid and nucleic acid synthesis, which require reducing power. It is the reduced form of NADP+, and it is involved in the conversion of CO2 into glucose.

Oxygen (O2): It is an essential molecule required for the process of respiration. It acts as the final electron acceptor in the electron transport chain, where it combines with electrons and protons to form water.

This generates the proton gradient needed for ATP synthesis during oxidative phosphorylation.

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Answer:
The empirical formula for C₄H₁₀0₆ is CH₂O
The empirical formula for Al(SO₃)1.5 is Al₂(SO₄)3
The empirical formula for CH₃ is already given.
The empirical formula for Fe(NO₃)3 is already given.

Explanation: Empirical formula is the simplest formula that gives the simplest whole number ratio of atoms in a compound.

To get the empirical formula, the given formula must be reduced to its simplest whole-number ratio. For this, divide each subscript by the largest common factor.

Hence, the empirical formulae for the given formulas are,

The empirical formula for C₄H₁₀0₆ is CH₂O
The empirical formula for Al(SO₃)1.5 is Al₂(SO₄)3
The empirical formula for CH₃ is already given.
The empirical formula for Fe(NO₃)3 is already given.

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The correct order of species based on their ability to act as an oxidizing agent is Au3+ > Fe2+ > Ni2+ > Na+.

The ability to act as an oxidizing agent varies among different species. In the given set of species, the order of their ability to act as an oxidizing agent from the best to the poorest is as follows:

Au3+ > Fe2+ > Ni2+ > Na+

Au3+ is the best oxidizing agent as it has the maximum tendency to accept electrons and undergo reduction.

Fe2+ is a better oxidizing agent than Ni2+ and Na+ because it can accept two electrons easily and undergoes reduction. Ni2+ is a weaker oxidizing agent than Fe2+ and Na+ as it can only accept electrons and undergoes reduction. Na+ is the poorest oxidizing agent as it has the least tendency to accept electrons and undergo reduction. It is the best reducing agent as it readily donates an electron to become Na.

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The type of atomic orbital that can be described as having 2 lobes of electron density separated by a nodal plane is the P orbital.

In atomic theory, an atomic orbital is a mathematical function that describes the behavior of one electron in an atom. It is a region in space with a high probability of locating an electron.

There are 3 types of orbitals available in each sub-shell of an atom. The sub-shell in each shell can be used to predict the number of orbitals.

There are 1 s-orbital, 3 p-orbitals, 5 d-orbitals, and 7 f-orbitals available in the first, second, and third shells, respectively. The type of atomic orbital that can be described as having 2 lobes of electron density separated by a nodal plane is the P orbital.

Each P orbital has two lobes of electrons located on either side of the nucleus separated by a nodal plane. The lobes can be polarized, making them more or less prominent depending on the situation.

This configuration provides the P orbital with a unique geometry and makes it highly suitable for molecular bonding.

The P orbital has a total of three different orientations. Each orientation corresponds to a different direction in space in which the lobes can be located. The three orientations are Px, Py, and Pz.

Each P orbital can hold a maximum of 2 electrons.

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The following 4 compounds ranked from weakest to strongest intermolecular forces are as follows: BF3 < BCl3 < PH3 < NH3.

Explanation: Intermolecular forces are the forces that exist between two or more molecules, which determine the physical characteristics of substances.

Intermolecular forces can be classified into different types, including dipole-dipole interactions, hydrogen bonding, and London dispersion forces.

These forces determine how the molecules interact with each other and how they behave under different conditions.

In the given compounds, BF3, BCl3, PH3, and NH3, each has a different arrangement of atoms that determines its intermolecular forces.

NH3 (Ammonia) is the strongest intermolecular force because it has hydrogen bonding.

PH3 has hydrogen bonding but it is weaker than NH3 as it is larger than NH3.

BCl3 and BF3 have London Dispersion forces which are weaker than hydrogen bonding.

The larger the molecule, the more electrons it has, and the stronger the London Dispersion forces.

In summary, the following 4 compounds ranked from weakest to strongest intermolecular forces are as follows:BF3 < BCl3 < PH3 < NH3

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In contrast to C3 plants, C4 plants have a different leaf structure and metabolic process. Carbon dioxide is first fixed in mesophyll cells of C4 plants.

where it is then transported to bundle sheath cells where it is broken down to release CO2 for the Calvin cycle. The key distinction between C4 and C3 plants is the division of carbon fixation and the Calvin cycle into various cells. C4 plants are more common in arid and semi-arid areas because they are more effective at photosynthesis in hot and dry conditions. In a typical C4 plant, the Calvin cycle and the first fixation of carbon dioxide take place in separate cells, the mesophyll cells, and the resulting four-carbon molecule is then transported to the bundle sheath cells in a C3 plant.

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Answer:

True.

The manipulated variable and the independent variable refer to the same thing in an experiment. It is the variable that is intentionally changed or manipulated by the experimenter to observe its effect on the dependent variable.