A certain weak acid, HA , with a Ka value of 5.61×10−6 , is titrated with NaOH .Part A: A solution is made by titrating 8.00 mmol (millimoles) of HA and 2.00 mmol of the strong base. What is the resulting pH?Part B: More strong base is added until the equivalence point is reached. What is the pH of this solution at the equivalence point if the total volume is 71.0 mL ?Express the pH numerically to two decimal places.

The grams of PbBr₂ formed when excess solution is added to 76.0 ml of 0.625 m solution of Pb(NO₃)₂ are 17.4325.

The balanced chemical equation for the process is,

Pb(NO₃)₂(aq) + BaBr₂(aq) → PbBr₂(s) + Ba(NO₃)₂(aq)

So, from the reaction, we can see that when one mole of Pb(NO₃)₂ reacts, one mole of PbBr₂ precipitate is formed.

It is given that 76ml of 0.625 M Pb(NO₃)₂ is reacting,

We know,

Moles = Molarity x volume (in liters)

Now, putting the value to find the moles of Pb(NO₃)₂ soluton,

Moles of Pb(NO₃)₂  = 76 x 0.625/1000

Moles of Pb(NO₃)₂  = 0.0475 moles.

So, the mole of the precipitate formed is 0.0475 Moles.

Now, we also know,

Moles = Formed mass/Molar mass.

Molar mass of PbBr₂ = 367 g/mol.

Moles of PbBr₂ = 0.0475 moles.

Formed mass of PbBr₂ = 367 x 0.0475

Formed mass of  PbBr₂ = 17.4325 Grams.

So,  17.4325 Grams of PbBr₂ is formed.

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The fuel value of plain M&M candies in kJ in a 42-g (about 1.5 oz) serving (approximately 1.5 oz) is 874.44 kJ

The calories does it provide = 208.99 Cal

In a pound of candy, there are:

96 g fat

320 g carbohydrate, and

21 g protein.

The serving size is m = 42 gr

To determine the worth of a single serving, we are asked.

To do this, we must first determine the candy's fuel worth per pound:

Fat = 96 g x 38 kJ/g

= 3648 kJ

Carbohydrate = 320 g x 17 kJ/g

= 5440 kJ

Protein = 21 g x 17 kJ/g

= 357 kJ

The sum of the fuel values for fat, carbs, and protein is the total fuel value per pound.

= 3648 kJ + 5440 kJ +  357 kJ

= 9445 kJ

Calculate the total fuel value per gram after determining the total fuel value per pound.

= 9445 kJ x (1 lb/ 453.6)

= 20.82 kJ/g

Next, determine how much fuel is in one serving:

This is expressed as the mass multiplied by the total fuel value per gram. Which is:

= 20.82 x 42 gr

= 874.44 kJ

So, the calories does it provide:

= 874.44 kJ/4.184

= 208.99 Cal

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A) Sugar B) Iodine C) Iodine number of grams of different solids in 100 g of the solvents - water, alcohol and chloroform

The term "solubility" describes how well a material (or "solute") dissolves in a particular solvent to form a solution.

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The process by which an atom or ion loses one or more electrons is known as oxidation, while the process by which an atom or ion gains one or more electrons is known as reduction.

The chemical processes in which electrons are transferred from one chemical to another. Redox reactions, also known as oxidation-reduction reactions, are the name given to these electron-transfer processes. The addition of oxygen or hydrogen to various compounds is another step in the oxidation and reduction reactions.

During oxidation processes,

1. Oxygen addition: C + O2 CO2 (oxidation of carbon)

2. Adding an electronegative element result in FeS (Fe + S) (oxidation of Iron)

3. Hydrogen removal: Br2 + H2S = 2 HBr + S (oxidation of sulphide)

4. Elimination of electropositive elements: I2 + 2 KOH + 2 KI + H2O (oxidation of iodide)

An oxidizing agent is something that causes oxidation. O2, S, Cl2, Br2, and H2O2 are oxidizing agents in the examples above.

Reduction responses include:

1. Hydrogen addition: N2 + 3 H2 2NH3 (reduction of nitrogen)

2. Electropositive element addition results in SnCl2 + 2HgCl2 becoming SnCl4 + Hg2Cl2 ( reduction of mercuric chloride)

3. Oxygen removal ZnO + C Zn + CO (reduction of zinc oxide)

4. Electronegative element removal using 2FeCl3 + H2 2FeCl2 + 2HCl (reduction of ferric chloride)

A substance that causes reduction is known as a reducing agent. HgCl2, C, and H2 are the reducing agents in the aforementioned cases.

A substance that goes through oxidation serves as a reducing agent, whereas a substance that goes through reduction serves as an oxidizing agent.

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Answer:

there are 3 bonded atoms in carbon monoxide and a total of 6 electrons

Answer: There are a total of two bonded atoms in carbon monoxide: one carbon atom and one oxygen atom. There are no lone pairs in carbon monoxide.

Explanation:  Carbon monoxide, or CO, is a chemical compound made up of one carbon atom bonded to one oxygen atom. The molecule has a linear shape, with the carbon atom at one end and the oxygen atom at the other end. There are a total of two bonded atoms in carbon monoxide: one carbon atom and one oxygen atom.

In terms of lone pairs, or non-bonding electrons, carbon monoxide has none. Lone pairs are pairs of electrons that are not involved in bonding, and they are typically found in the outermost electron shell of an atom. In carbon monoxide, all of the electrons are either bonded to the other atom in the molecule or are involved in bonding to that atom. Therefore, there are no lone pairs in carbon monoxide.

In order to create sets of comparable orbitals that are correctly orientated to form bonds, the localised valence bonding theory employs a mathematical process known as hybridization.

hybridization combines atomic orbitals that are same in energy but not equal. Because these new combinations are made by combining (hybridising) two or more atomic orbitals from the same atom, they are known as hybrid atomic orbitals. The 2s orbital of beryllium and any one of the three degenerate 2p orbitals can be combined to create two equivalent orbitals in BeH2. Using the difference and total of the Be 2s and 2pz atomic orbitals.

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Aristotle was not wrong that he thought that the matter was made up of four elements, earth, water, the air and the fire. the mater is composed of the tiny particles that are atoms, molecules.

The matter will exits in the four states the solid state , the liquid state , the gas state and the plasma state. The matter is the thing which has the mass and will occupy the space. the matter is composed of the tiny particles that are  atoms of the group of the atoms called as the molecules. an atom is the smallest unit of the element.

Thus, the matter is composed of the tiny particles ,the  atoms and the molecules.

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Electron(s) are lost during oxidation, and the oxidation state is raised.

While reduction includes the acquisition of electrons, oxidation entails the loss of electrons.

This is in line with how oxidation and reduction are defined.

Redox reaction refers to any process in which oxidation and reduction take place simultaneously. When reactants are transformed into products in an oxidation-reduction (redox) reaction, electrons are transferred from one element to another. The change in oxidation values from the reactant side to the product side indicates the transfer of electrons.

As a result, choice D is the right response.

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There are 45 atoms.

Each of the 3 oxygen atoms gains 2 electrons from 2 Al atoms, and each Al atom donates 3 electrons to 3 oxygen atoms. In this process each Al atom becomes an Al3+ ion and an oxygen atom. O2 ion got two electrons. Or the formula is Al2O3.

The bonding pattern of a hybridized carbon atom consists of two single bonds to two atoms and one double bond to the third atom, with a total of eight valence electrons around the bonded carbon atom. give. Atoms with all single bonds are sp3 hybridized. The best examples are alkanes. All carbon atoms in alkanes are sp3 hybridized with tetrahedral geometry.

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The rate constant for H2SO4 is 1.02 x 10-2 and the rate constant for Na2C2O4 is 5.3 X 10-5.

Ka2  is the second rate dissociation constant.

Kb2 is the second base dissociation constant.

H2SO4 is a di-basic acid. Whose Step wise dissociation is given below :

H2SO4 = H++ HSO4- ---(1)

Where the rate constant is ka1 .

Now Again HSO4-  will dissociates in the following way :

HSO4- = H+ + SO42- -----(2)

Where the rate constant is Ka2 .

So , the equation for Ka2 is :

Ka2=[H+][SO42-]/[HSO4-]

The rate constant is 1.02 x 10-2.

Similarly step-wise dissociation of Disodium oxalate (Na2C2O4)  is

Na2C2O4 = NaC2O4- + Na+ -----(1)

Second dissociation equation is

NaC2O4- = C2O42- + Na+ ----(2)

So , the rate constant for the second equation is:

Ka2=[Na+][C2O42-]/[NaC2O4-]

The rate constant is  5.3 X 10-5.

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Electron groups around a central atom tend to spread out as much as possible because of the electron-electron repulsion principle, also known as the Pauli exclusion principle. According to this principle, electrons in an atom tend to occupy different energy levels, or orbitals, to minimize the repulsive interactions between them.

When electron groups are spread out as much as possible, the energy of the system is minimized, and the atoms are more stable. This is because the repulsive forces between the electrons are reduced when they are farther apart. This is known as the octet rule, which states that atoms tend to gain or lose electrons in such a way as to have eight valence electrons in their outermost shell, which is the most stable configuration.

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Empirical formula units is 2 and the molecular formula is CxHyOz.

Molar mass-The molar mass of a chemical compound is determined by dividing its mass by the quantity of that compound, expressed as the number of moles in the sample, measured in moles. The molar mass of a substance is a bulk attribute rather than a molecular one.Calculate the molar mass of a substance by adding the molar masses of its constituent atoms.

There are 40.0 in 100 g of the unknown.

40.0⋅g/12.011⋅g⋅mol−1C

6.7⋅g/1.00794⋅g⋅mol−1 H and

53.5⋅g/16.00gmol−1  

We divide by to get C : H : O.

=3.33:6.65:3.34

. We get an empirical formula of C H 2 O by dividing each elemental ratio by the LOWEST number, which is close enough to WHOLE numbers.

Now the molecular formula is always a multiple of the empirical formula; i.e.

(EF)n=MF.

So 60.0⋅g.mol−1=n×(12.011+2×1.00794+16.00)g⋅mol−1.

Clearly n=2, and the molecular formula is×(CH2O) =CxHyOz.

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This amount of solute would be provided by 2.5 grams of a 10.0% solution.

% (w/v) formula:

[tex]% (\frac{w}{v}) = \frac{grams solute}{mL of solution} *100[/tex][tex](\frac{w}{v})[/tex]%[tex]= \frac{grams solute}{mLof solution} *100[/tex]

[tex]10[/tex]% [tex]NACl(\frac{g}{mL})= \frac{grams NaCl}{25mL} *100[/tex]

To calculate the mass in grams of NaCl required to create a 10% (w/v) NaCl solution, divide 10% by 100 and multiply the result by 25.

[tex]0.1*25 = 2.5g[/tex]

Salt, commonly known as sodium chloride (NaCl), is a substance that our body needs in order to absorb and transport nutrients, regulate blood pressure, maintain fluid balance, convey nerve messages, and contract and relax muscles.

Salt, or sodium chloride, accounts for about 75 to 90 percent of the sodium we consume. Our bodies require sodium, an essential mineral found in salt, for processes including blood pressure regulation and nutrition absorption. In addition to using salt to season food, clean household goods, and treat some medical conditions. Greater health issues like high blood pressure, heart disease, and kidney disease can be brought on by consuming too much salt. Your chance of developing those illnesses can be decreased by consuming less salt and consuming more potassium.

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10.36 is the ph of a solution made by dissolving 1.9 g of k2co3 and 7.9 g of khco3 in 500. ml of water

Mass of K2CO3 = 1.9 g

Moles of K2CO3 = ( Mass / Molar mass ) = ( 1.9 g / 138.205 g / mol ) = 0.031 mol

Mass of KHCO3 = 7.9 g

Moles of KHCO3 = ( Mass / Molar mass ) = ( 7.9 g / 100.115 g / mol ) = 0.0789 mol

Volume of solution = 500 mL = 0.5 L

[ HCO3- ] = 0.078 mol / 0.5 L = 0.156 M

[ CO32-] = 0.031 mol / 0.5 L = 0.062 M

Ka for HCO3- = 4.7 x 10 -11

pKa = 10.32

pH = pKa + log [CO32-] / [HCO3-]

pH = 10.32 + log ( 0.062/0.156 ) = 10.32 - 0.4 = 10.31

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The half-life of the radium isotope ra-226 is approximately 1,599 years. After 800 years, the remaining amount of the isotope is 70.71% of its initial quantity.

The decay formula is given by:

N(t) = No . (1/2)^(t/T)

Where:

N(t) = remaining quantity of the substance at time t

No = initial quantity

t = elapsed time

T = half-life

In the given problem:

t = 800 years

T = 1599 years

Therefore,

N(t) = No . (1/2)^(800/1599)

N(t) = 0.7071 No

N(t)/No = 0.7071 = 70.71%

Hence, the remaining amount of the isotope is 70.71%

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An enzymatic reaction can move at a maximum speed of 666.67 umol-1s-1.

The Michaelis-Menten equation, developed by Briggs and Haldane, best captures the enzyme equation by modeling the rate of enzymatic reactions by coupling the rate of product creation to the concentration of substrate, as shown below.

[tex]v_{i} = \frac{v_{max} * [S]}{k_{m}+ [S] }[/tex]

Where v denotes the reaction’s speed, Vmax denotes the system’s maximum rate of growth, [S] denotes the substrate’s concentration and [tex]k_{m}[/tex] denotes the Michaelis constant.

[tex]500= \frac{v_{max}*75 }{25+75}[/tex]

[tex]500= \frac{v_{max} * 75}{100}[/tex]

[tex]500*100= v_{max} *75[/tex]

[tex]\frac{50000}{75} = v_{max}[/tex]

[tex]v_{max} = 666.67[/tex]

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They are known as anions when they are negatively charged and as cations when they are positively charged. Consequently, the response was: Hg(NO3)2 + Na2SO4 HgSO4 + 2NaNO3.

In an aqueous solution, the following reaction occurs: Na2S04+Hg2(N0,)2 ----> Hg2S04 + 2NaN0, Cross out the spectator ions after comparing the reactant and product sides of the revised reaction. Observer ions are any dissolved ions that exhibit the same form on both sides. If everyone is a spectator, then there is no reaction.

When comparing the solutions before and after the reaction, we can see that both solutions contain sodium and nitrate ions. They experience zero chemical alterations. These ions are known as spectator ions since they have no involvement in the chemical reaction (they just "watch").

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9.73 g of lead(iv) chloride contains enough cl- ions to make 5.31 g of magnesium chloride.

Given data:

Mass of  lead(iv) chloride = 9.73 g

Molar mass of 9.73 g = 278 g/mol

Mole can be determine by using the formula:

Mole = mass / molar mass

Moles = 9.73 g / 278 g/mol

Moles = 0.035

If 9.73 g of lead(iv) chloride contains 0.035 mole of lead(iv) chloride then 5.31 g of magnesium chloride

The formula is Mgcl2 ,so the mole will be 24 + (35.5 x2) = 95.

So 2x 35.5 = 71g of Cl will be required to make 95g of Mgcl2

So 1 gram of Cl = 95/71 = 1.34g Mgcl2

So 3.95g Cl =1.34 x 3.95 = 5.28gram

Therefore, cl- ions to make 5.31 g of magnesium chloride.

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The balanced equation for this reaction is

CCl2S2 + 4Cl2 -> CCl4 + S2Cl2

The coefficient in front of chlorine is 4. This means that 4 moles of chlorine are required to react with 1 mole of carbon disulfide. This reaction follows the Law of Conservation of Mass, meaning that matter is neither created nor destroyed during a chemical reaction.

Chlorine is added to the reaction to ensure that the same amount of chlorine atoms are present on both sides of the equation. The chlorine atoms are necessary to convert the carbon disulfide into carbon tetrachloride and disulfur dichloride.

The chlorine atoms act as an oxidizing agent, breaking down the molecules of carbon disulfide and rearranging them into new compounds.

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The nuclear equation shown is completed as follows:

²¹⁴₈₂Pb ---> ⁰₋₁e + ²¹⁴₈₃Bi

The correct option is B.

A nuclear equation is an equation that represents or shows a nuclear reaction.

particles found nuclear reaction is a reaction in which reaction changes occur in the atomic particles found within the nucleus of a na atom.

There are two types of nuclear reactions;

nuclear fusion - the fusion of the atoms of two sammlerf nuclei to form larger nuclei

nuclear fission - the splitting of the nucleus of a large atom to produce two or smaller atoms.

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A small cube of solid uranium metal, measuring about two inches on each side and weighing less than 2.5 kilos, has been housed at the Pacific Northwest National Laboratory (PNNL) for many years.

A Heisenberg cube is what?

More than 600 "Heisenberg cubes," named after Werner Heisenberg, one of the German physicists who developed them, were taken from a top-secret underground laboratory at the end of World War II and brought to the United States. These cubes were essential to the Nazis' plans to build both a nuclear reactor and an atomic bomb.

Is uranium available for purchase?

However, the truth is that you may purchase uranium ore without a special permit from websites like Amazon or Ebay. The most prevalent isotope of the element, uranium-238, is only purchased for research purposes.

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A solution that contains the chemical compounds CsF and HF will serve as a buffer.

When a weak acid, as well as its conjugate base or weak base as well as its conjugate acid, are combined, buffer solutions are created that serve to maintain the solution's pH level even when a little amount of a strong acid is added.

Except for CsF and HF, all of the aforementioned pairings will create a buffer solution since CsF is a weak base whereas F is the organic compound with the formula of HF acid.

A buffer is a substance that can withstand a pH shift when acidic or basic substances are added. It can maintain the solution's pH by neutralizing modest quantities of additional acid or base.

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13.755 gram of cl2 is deposited in the electrolysis of NaCl which is calculated using Faraday's law.

Electrolysis is defined as the process by which electric current is passed through a substance to effect a chemical change. The chemical change is one in which the substance loses or gains an electron.

Current, C = 4.80 amp

time, T = 130 minutes

            = 130 * 60 = 7800 seconds

Molar mass of cl2 is 70.906.

Equivalent mass of cl2 is,

      E=  mass of cl2 / atomicity = 70.906 / 2 = 35.453 gram.

Here apply the faraday's law. The amount of substance that undergoes a chemical reaction at an electrode during electrolysis is proportional to the quantity of electricity passed through an electrolyte. W is the weight of the substance, Q is the amount of charge passed, I is current, t is time for which current flows, k is proportional constant.

  w= EIT / 96500

     = 35.453 * 4.80 * 7800 / 96500

     = 13.755 g of cl2 deposited.

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If boiling point of liquid nitrogen is 77.0K then the temperature in Celsius scale is -196°C and in Fahrenheit scale is -321°F.

Relation between Celsius and Kelvin: 

Both Celsius and Kelvin are measures of temperature. 0 Celsius is the freezing point of water and 100 Celsius is the boiling point. Whereas Kelvin is a measure of the internal energy of a material. 0K is -273.15°C.

the boiling point of liquid nitrogen is 77.0 k.

K = 273+C 

77= 273+C 

C= -196°C 

Relation between Celsius and Fahrenheit: 

Fahrenheit temperature scale, scale based on 32° for the freezing point of water and 212° for the boiling point of water, the interval between the two being divided into 180 equal parts. The Fahrenheit temperature scale is used in the United States; the Celsius, or centigrade, scale is employed in most other countries and for scientific purposes worldwide.

C/5 = (F-32)/9 

-196/5 = (F-32)/9

F= -320.8=-321°F

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The compound treatment on with silver nitrate does not result in the precipitation of silver chloride. the formula of the compound is [Pt(NH₃)₂Cl₂].

The contains the platinum(II) and the two ammonia molecules per the platinum. the compound contains the chloride ions per mole of the platinum. the compound does not give precipitate of silver chloride on treating with the silver nitrate is [Pt(NH₃)₂Cl₂].

The compound will react with the silver nitrate if the Cl is out of the coordination sphere. the  NH₃ is the monodentate ligand and Cl is also the monodentate ligand. the total ligand is 4 coordinated ligand.  the oxidation state of Pt is +2

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The molecular dipole moments of the substituents, which are used to quantify their effect on electron donating or withdrawing, may be associated with the deactivation of the aromatic ring toward electrophilic substitution.

A substituted ring with an activating group undergoes the EAS reaction more quickly than benzene. A substituted ring with a deactivated group, on the other hand, moves more slowly than benzene. By using resonance or inductive electron donation, activating groups accelerate the EAS reaction. The reaction rate with regard to benzene is increased or decreased by the group(s) linked to the aromatic ring. the new substituent's entrance position. Activating and deactivating groups, respectively, affect the rate of the electrophilic aromatic substitution process with regard to benzene..

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Answer:

It is really easy and I don't want you to get in trouble for using other people's work I'm not saying i can't help but I think its wrong no offense  

Explanation:

Nothing would happen if the solutions were switch so that the first incubation was in the pH 8 solution and he second one was in the pH 4 solution.

The H+ gradient would be in the wrong direction, ATP synthase would not work.

pH is a measure of how acidic/basic water is. The range goes from 0 to 14, with 7 being neutral. pHs of less than 7 indicate acidity, whereas a pH of greater than 7 indicates a base. pH is really a measure of the relative amount of free hydrogen and hydroxyl ions in the water.

pH is an important quantity that reflects the chemical conditions of a solution. The pH can control the availability of nutrients, biological functions, microbial activity, and the behavior of chemicals.

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When 1.9 mol of copper (ii) hydroxide decomposes to form copper (ii) oxide and water, moles of water that formed are 1. 9 moles

The moles that formed can be calculated as follows:

first we should write the balanced reaction

Cu(OH)₂ → CuO + H₂O

The following numbers of moles of each component are involved in the reaction according to reaction stoichiometry, which describes the relationship between the amounts of reagents and products in a chemical reaction, with unitary method we can calculate the moles of H₂O:

Cu(OH)₂: 1 mole

CuO: 1 mole

H₂O: 1 mole

so, 1 mole of Cu(OH)₂ produce 1 mole of H₂O

If 1.9 mol of copper (ii) hydroxide decomposes to form copper (ii) oxide and water so the moles of H₂O is

Moles H₂O = 1/1 x mole of Cu(OH)₂ = 1/1 x 1.9 mol = 1.9 moles

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The student's conclusion is not necessarily correct. The concentration of a solution is determined by the amount of solute (in this case, copper sulfate) present in a given amount of solvent (in this case, water). When the student added solution B to solution A, the total volume of the solution increased from 50 cm³ to 150 cm³, while the total amount of copper sulfate remained constant at 15 g. This means that the concentration of the new solution may be lower than that of the original solutions, since the same amount of solute is now present in a larger volume of solvent. To determine the actual concentration of the new solution, the student would need to measure the amount of copper sulfate present in a given volume of the solution and compare it to the original solutions.