solid magnesium aqueous hydrochloric acid aqueous magnesium chloride hydrogen gas balanced equation

The standard change in Gibbs energy at 25 degree Celsius is  490.6 °C. for given equilibrium partial pressure  .

The Gibbs energy is the thermodynamic potential that is minimized when a system reaches chemical equilibrium at constant pressure and temperature when not driven by an applied electrolytic voltage. Its derivative with respect to the reaction coordinate of the system then vanishes at the equilibrium point.

Using the formula

ΔG° =  - R × T ln K

WHERE R=  8.3144598 J⋅mol⁻¹⋅K⁻¹.

T = 298 K

K = 0.82

SOLVING ,

The standard change in Gibbs energy at 25 degree Celsius is  490.6 °C.

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The empirical formula, CH2O9(menthol) is multiplied by 5 to get the molecular formula, C10H20O.The empirical and molecular formula for menthol are CH2O and C10H20O, respectively.

The molecular formula for menthol is C5H10O.

This can be determined by dividing the molar mass of the empirical formula (156.26 g/mol) by the molar mass of CO2 (44.01 g/mol). This gives a ratio of 3.55, which is equal to the ratio of C atoms in the empirical formula, C10H20O.

Therefore, the molecular formula is C5H10O.
Given:

Menthol is composed of C, H, and O0.1005g sample of menthol is combusted and produces0.2829g of CO2 0.1159g H2O

1. Find: Empirical and molecular formula for menthol.

Let's first calculate the number of moles of CO2 produced. The balanced equation for combustion of menthol is:

C10H20O(s) + 12O2(g) → 10CO2(g) + 10H2O(l)

From the above equation, we can see that for 10 moles of CO2 produced 1 mole of menthol is required.

2. By taking the number of moles of CO2 produced, we can calculate the number of moles of menthol burned.

Moles of CO2 = 0.2829g / 44.01g/mol= 0.00643 mol

C10H20O(s) + 12O2(g) → 10CO2(g) + 10H2O(l)

From the balanced equation,1 mole of C10H20O requires 10 moles of CO2

Moles of C10H20O burned = 10 * 0.00643= 0.0643 mol

Next, we can calculate the number of moles of H2O produced.

Moles of H2O = 0.1159g / 18.015g/mol= 0.00643 mol

C10H20O(s) + 12O2(g) → 10CO2(g) + 10H2O(l)

From the balanced equation,1 mole of C10H20O requires 10 moles of H2O

Moles of C10H20O burned = 10 * 0.00643= 0.0643 mol

3. Now we can calculate the empirical formula of menthol. The empirical formula can be calculated as follows:

Empirical formula = CH2O (Divide all moles by smallest moles) The molecular weight of CH2O = 30 g/mol

The empirical formula mass of the compound is:

mass = (12.011 + 2*1.008 + 15.999) = 30.026

Empirical formula mass of CH2O is 30.026g/mol, and the given sample weighs 0.1005 g.
The number of empirical formula units in the sample is 0.1005 g / 30.026 g/mol = 0.003348Units.

Empirical formula = CH2OThe empirical formula weight of menthol is CH2O, which is equal to 30.026g/mol.

4. To find the molecular formula, we need to know the molecular weight of the menthol. We can calculate it as follows:

Molecular formula mass = Empirical formula mass x n

Where n = integer Molecular formula mass of menthol is 156 g/mol, and the empirical formula mass is 30.026 g/mol.

So, n = 156 g/mol ÷ 30.026 g/mol = 5.192

Thus the empirical formula, CH2O is multiplied by 5 to get the molecular formula, C10H20O.The empirical and molecular formula for menthol are CH2O and C10H20O, respectively.

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The claim was correct . All elements  have same number of particles in one mole and have different number of particles  in a mole based on atomic number .

In the International System of Units, the mole (symbol mol) is the unit of substance amount (SI). The amount of substance is a measurement of how many elementary entities of a given substance are present in an object or sample. An elementary entity can be an atom, a molecule, an ion, an ion pair, or a subatomic particle such as an electron, depending on the substance. For example, despite having different volumes and masses, 10 moles of water (a chemical compound) and 10 moles of mercury (a chemical element) contain equal amounts of substance, and the mercury contains exactly one atom for each molecule of water.

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The empirical formula of a molecule containing 65.5% carbon, 5.5% hydrogen, and 29% oxygen is CH2O.

To calculate this, you need to first convert the percentage composition into mass composition. This is done by multiplying the percentages by the molecular weight of each element.

Carbon: 65.5% x 12 g/mol = 0.786 g/mol
Hydrogen: 5.5% x 1 g/mol = 0.055 g/mol
Oxygen: 29% x 16 g/mol = 0.464 g/mol
Now that you have the mass composition, you can calculate the moles of each element by dividing the mass of each element by its molar mass.
Carbon: 0.786 g/mol / 12 g/mol = 0.065 mol
Hydrogen: 0.055 g/mol / 1 g/mol = 0.055 mol
Oxygen: 0.464 g/mol / 16 g/mol = 0.029 mol
Finally, divide each element's moles by the smallest moles to get the empirical formula.

Carbon: 0.065 mol / 0.029 mol = 2.24 = 2 mol
Hydrogen: 0.055 mol / 0.029 mol = 1.90 = 1 mol
Oxygen: 0.029 mol / 0.029 mol = 1.00 = 1 mol
Therefore, the empirical formula of the molecule is CH2O.

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Answer:

4897 J

Explanation:

The heat transferred to the surroundings, q_surr, can be calculated using the equation:

q_surr = -q_rxn = -CmΔT

where C is the specific heat capacity of the mixture (assumed to be the same as water, 4.184 J/g°C), m is the mass of the mixture (which we can calculate using the density, assuming that the volumes are additive), and ΔT is the change in temperature (in Celsius).

First, let's calculate the mass of the mixture:

density of water = 1.00 g/cm^3

volume of mixture = volume of acid + volume of base = 106 mL + 157 mL = 263 mL = 0.263 L

mass of mixture = density of water x volume of mixture = 1.00 g/cm^3 x 0.263 L = 263 g

Next, let's calculate the change in temperature:

ΔT = final temperature - initial temperature = 27.29°C - 22.94°C = 4.35°C

Now we can calculate the heat transferred to the surroundings:

q_surr = -CmΔT

q_surr = -(4.184 J/g°C) x (263 g) x (4.35°C)

q_surr = -4897 J

Note that the negative sign indicates that heat is lost by the system to the surroundings. Therefore, the heat transferred to the surroundings, q_surr, is 4897 J.

The completed table of maximum moles of water, limiting reactant and excess reactant is as follows:

Q: 6 moles, O₂, 1 mole H₂

R: 6 moles, O₂, 2 moles H₂

S: 5 moles, none, none

T: 5 moles, H₂, 2.5 moles O₂

U: 8 moles, H₂, 2 moles O₂

The mole ratio of the reaction of hydrogen and oxygen to form water is obtained from the equation of the reaction.

The equation of the reaction is given below:

2 H₂ + O₂ --> 2 H₂O

The mole ratio of hydrogen to oxygen is 2:1 in both the water molecule and the reactants, hydrogen gas (H2) and oxygen gas, as can be seen from the balanced equation (O2). 

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Answer: There are 3019.2 atoms of iron.

Answer:

Explanation:

Iron is a ductile, malleable, silver-white metallic element, scarcely known in a pure condition, but much used in its crude or impure carbon-containing forms for making tools, implements, machinery, etc. Symbol: Fe; atomic weight: 55.847; atomic number: 26; specific gravity 7.86 at 20°C.

1 mol contains [tex]=6.02\times10^{23}[/tex] particles, whether it be atoms, ions, molecules or whatever (Avogadro's number).

So you just divide:

[tex]\frac{2.96\times10^{20}}{6.02\times10^{23}}[/tex] = = 4.9169435215947 × 10^-4

The maximum number of electrons that can occupy the 1s sub-shell is 2, the 3p sub-shell is 6, the 3d sub-shell is 10, and the 6g sub-shell is 32.

For the 1s sub-shell, due to the Pauli Exclusion Principle, two electrons of opposite spin can exist in the same orbital. This means that there is a maximum of two electrons that can occupy the 1s sub-shell. For the 3p sub-shell, three orbitals exist with a maximum of two electrons each. Since two electrons of opposite spin can occupy each orbital, there is a maximum of six electrons that can occupy the 3p sub-shell. For the 3d sub-shell, five orbitals exist with a maximum of two electrons each. Since two electrons of opposite spin can occupy each orbital, there is a maximum of 10 electrons that can occupy the 3d sub-shell. Finally, for the 6g sub-shell, seven orbitals exist with a maximum of two electrons each. Since two electrons of opposite spin can occupy each orbital, there is a maximum of 32 electrons that can occupy the 6g sub-shell.

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The acid in the reaction would donate a proton and that would be HNO2.

An acid in a chemical reaction can be identified by the presence of hydrogen ions (H+): Acids are compounds that produce hydrogen ions when dissolved in water. In a chemical reaction, an acid may donate a hydrogen ion to another compound or accept a pair of electrons from a base.

When we look at the reaction, we can see that the specie that has given out the replaceable hydrogen ion is HNO2 thus it is the acid in the reaction.

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A few statements may be true regarding a biochemical oxidation-reduction (redox) reaction. The statements are as follows: A redox reaction occurs when there is a transfer of electrons between molecules or atoms.

The electron donor becomes oxidized, and the electron acceptor is reduced, causing a transfer of energy. A redox reaction produces ATP, which is the primary energy currency of the cell. Oxidation and reduction are complementary reactions that occur simultaneously in the same reaction, resulting in the release of energy. Redox reactions are vital in metabolic pathways, and the electron carriers NAD+ and FAD+ are essential in these reactions. Oxygen is frequently used as a final electron acceptor in redox reactions. Redox reactions can also occur in non-cellular environments, such as photosynthesis, respiration, and combustion. The significance of redox reactions is enormous, and they play an essential role in sustaining life on earth. They help in generating energy, breaking down complex molecules, synthesizing molecules, and many other cellular processes.

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The major organic product of the condensation of ammonia or a primary amine with the carbonyl group of an aldehyde or ketone is an imine.

A functional group or organic substance with a carbon-nitrogen double bond (C=N) is known as an imine. A hydrogen atom or an organic group may be joined to the nitrogen atom. (R). The carbon atom is connected to two more single bonds. Imines are present in numerous processes and are frequently found in manufactured and naturally occurring chemicals.

The five core atoms for ketimines and aldimines, C2C=NX and C(H)C=NX, respectively, are coplanar. The sp2-hybridization of the mutually double-bonded nitrogen and carbon atoms yields planarity. For nonconjugated imines, the C=N distance is 1.29-1.31, whereas for conjugated imines, it is 1.35. The C-N distances in amines and nitriles, on the other hand, are 1.47 and 1.16, respectively. Slow rotation occurs around the C=N bond. E- and Z-isomers were detected using NMR spectroscopy of aldimines have been detected. Owing to steric effects, the E isomer is favored.

An imine is formed when a primary amine reacts with a carbonyl group (C=O) of an aldehyde or ketone to form a new C-N bond. This reaction is known as a condensation reaction, as it involves the loss of a small molecule (e.g. water) to form the product.

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The correct questions is :

What  is the major organic product of the condensation of ammonia or a primary amine with the carbonyl group of an aldehyde or ketone?

Its atomic radius increases form top to bottom inside a group, then decreases from left and right across a period. As a result, francium is indeed the largest element while helium is the smallest.

Atomic radii inside the periodic table decrease across a row form left to right and increase across a column from top to bottom. Due to these two patterns, the periodic table's lower left and upper right corners, respectively, contain the largest and smallest atoms.

The atomic radius grows form top to bottom inside a group and decreases form left to right during a period, as seen in the images below. As a result, francium is indeed the largest element while helium is the smallest.

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a. The atom with the smaller atomic size is: Nitrogen

a. The atom with the smaller atomic size is: Arsenic.

Atomic size, also known as atomic radius, is the distance between the nucleus of an atom and its outermost electrons. It is typically measured in picometers (pm) or angstroms (Å). The atomic size of an element can be calculated by finding the distance between the nucleus and the outermost electron shell of an atom of that element. This distance can be determined using various methods, including X-ray diffraction and spectroscopy. The atomic size of elements generally decreases from left to right across a period and increases from top to bottom down a group in the periodic table.

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Answer:

First, we need to calculate the change in temperature:

ΔT = final temperature - initial temperature

ΔT = 85 °C - 35 °C

ΔT = 50 °C

Next, we can use the following formula to calculate the heat energy required:

Q = m·C·ΔT

where Q is the heat energy in calories, m is the mass of the sample in grams, C is the specific heat in cal/g °C, and ΔT is the change in temperature in °C.

Plugging in the given values, we get:

Q = 35.0 g · 0.108 cal/g °C · 50 °C

Q = 189.0 calories

Therefore, 189.0 calories are required to raise the temperature of the sample from 35 °C to 85 °C

The pH of 0.335 M trimethylammonium chloride, (CH3)3NHCI is approximately 5.676.

What is pH?

To find the pH of the solution, we need to first determine if (CH3)3NHCI acts as an acid or base. Since (CH3)3NHCI is a salt composed of a weak base, trimethylamine, and a strong acid, hydrochloric acid (HCI), it will undergo hydrolysis in water.

The hydrolysis reaction is given by:

(CH3)3NH+ (aq) + H2O (l) ⇌ (CH3)3N (aq) + H3O+ (aq)

The Kb expression for the equilibrium reaction is:

Kb = [ (CH3)3N ] [ H3O+ ] / [ (CH3)3NH+ ]

Since (CH3)3NH+ and HCl dissociate completely in water, the initial concentration of (CH3)3NH+ is equal to the concentration of (CH3)3NHCI, which is 0.335 M.

Using the Kb value given, we can solve for the concentration of H3O+:

Kb = 6.3 x [tex]10^{-5}[/tex] = [ (CH3)3N ] [ H3O+ ] / 0.335

[ H3O+ ] = Kb x (CH3)3NH+ / (CH3)3N

[ H3O+ ] = 6.3 x [tex]10^{-5}[/tex] x 0.335 / 1

[ H3O+ ] = 2.1095 x [tex]10^{-6}[/tex] M

Finally, we can calculate the pH using the expression:

pH = -log [H3O+]

pH = -log (2.1095 x [tex]10^{-6}[/tex])

pH = 5.676

Therefore, the pH of the solution is approximately 5.676.

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Complete question is: The pH of 0.335 M trimethylammonium chloride, (CH3)3NHCI is approximately 5.676.

If we use the Gizmo to find the freezing, melting, and boiling points of water at 5,000 meters (16,404 feet) then,

Freezing point: 32 ºF (0ºC)

Melting point: 32 ºF (0ºC)

Boiling point: 203°F (95°C)

The freezing point is defined as the temperature at which a liquid becomes a solid. Increased pressure usually raises the freezing point with the melting point of the solid. The boiling point of a pure substance is defined as the temperature at which the substance transitions from a liquid to the gaseous phase. At the boiling point the vapor pressure of the liquid is equal to the applied pressure on the liquid. The melting point of a substance is defined as the temperature at which the substance changes from a solid to a liquid.

Melting occurs at a single temperature for the pure substances. The normal and average melting point and boiling point of water at 1 atmospheric pressure are 0°C and 100°C respectively. Decreasing the pressure under 1 atm. will lower the boiling point since the external pressure will be lower so it will become equal with the vapor pressure at a lower temperature.

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Answer:

As the number of gas particles increases, the frequency of collisions with the walls of the container must increase. This, in turn, leads to an increase in the pressure of the gas. Flexible containers, such as a balloon, will expand until the pressure of the gas inside the balloon once again balances the pressure of the gas outside.

Explanation:

The R f values for compounds A, B, and C on a silica gel TLC plate developed in hexanes would be determined by measuring the distance each compound traveled compared to the distance the solvent traveled.

a) There is a 4 cm gap between the origin and the solvent front. The Rf value for spot A is[tex]\frac{1.5}{4}= 0.375[/tex], because it travelled 1.5 cm. Due to the 3.5 cm movement of Spot B, its Rf is[tex]\frac{3.5}{4} = 0.875[/tex]. Spot C shifted 3 cm, making its Rf [tex]\frac{3}{4} = 0.75[/tex].

b)Due to its shorter travel distance than the other two compounds, compound A is the most polar. Recall that polar substances adhere to the adsorbent more readily, move less, and have a lower Rf value.

c)Hexanes is less polar than acetone as a solvent. Each of the three compounds would move more quickly if the same method were employed to elute them.The chemicals can be removed from the polar adsorbent more effectively with a more polar eluting solvent. Each compound would have a higher Rf value if acetone were used to elute the TLC plate as opposed to hexanes because each compound travels more quickly.

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In comparison to 310.0 K, the reaction happens 1.28 times faster at 314 K.

A high K value (higher than 1) denotes an equilibrium with more products than reactants, whereas a low K value (less than 1) denotes an equilibrium with more reactants than products.

The Arrhenius equation, which connects the rate constant (k) to the activation energy (Ea) and temperature (T), can be used to determine how much faster the reaction happens at 314 K than it does at 310.0 K. k = A * exp(-Ea / (R * T))

where T is the temperature in Kelvin, R is the gas constant, and A is the preexponential factor.

For this reaction, we can assume that the pre-exponential component is fixed and that the sole variable is temperature.

exp[(Ea / R) * (1/T1 - 1/T2)] = k2 / k1

where Ea is the activation energy, R is the gas constant, k1 is the rate constant at 310.0 K, and k2 is the rate constant at 314 K.

k2 / k1 = exp[(50.0 kJ/mol / (8.314 J/mol•K)) * (1/310.0 K - 1/314 K)] is the result of substituting the provided numbers.

If we condense this phrase, we get:

k2 / k1 = 1.28

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There are approximately 0.005302 moles of NOs in 3.19 × 10^16 molecules.

Mole is an SI unit used to measure the amount of any substance.

To calculate the number of moles of NOs in 3.19 × 10^16 molecules, we need to use Avogadro's number, which is 6.022 × 10^23 molecules per mole.

First, we need to convert the number of molecules to moles using the formula:

moles = molecules / Avogadro's number

moles of NOs = 3.19 × 10^16 molecules / 6.022 × 10^23 molecules per mole

moles of NOs = 0.005302 moles (rounded to 4 significant figures)

Therefore, there are approximately 0.005302 moles of NOs in 3.19 × 10^16 molecules.

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The number of moles present in 3.19×10¹⁶ molecules of nitrogen dioxide, NO₂ is 5.30×10⁻⁸ mole

The number of moles present in 3.19×10¹⁶ molecules of NO₂ can be obtained by using the Avogadro's hypothesis as illustrated below:

From Avogadro's hypothesis,

6.022×10²³ molecules = 1 mole of NO₂

Therefore,

3.19×10¹⁶ molecules = 3.19×10¹⁶  / 6.022×10²³

3.19×10¹⁶ molecules = 5.30×10⁻⁸ mole of NO₂

Thus, we can conclude that the number of mole is 5.30×10⁻⁸ mole

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Answer:

Explanation:

2-bromopropane is the major product because the reaction mechanism involves the formation of the most stable carbocation intermediate. When hydrogen bromide reacts with propene, the hydrogen atom from HBr adds to the carbon atom of the double bond that has fewer hydrogen atoms attached, resulting in the formation of a carbocation intermediate. The intermediate can either form 1-bromopropane or 2-bromopropane depending on the position of the carbocation. The 2-bromopropane is the major product because the secondary carbocation formed in this case is more stable than the primary carbocation formed in the case of 1-bromopropane.

To test for an alkene, bromine water can be used. When an alkene reacts with bromine water, the bromine molecule adds across the double bond, forming a colorless dibromoalkane product. The mechanism for the reaction between hex-1-ene and bromine involves the formation of a cyclic bromonium ion intermediate, followed by the attack of water on the intermediate, resulting in the formation of the dibromoalkane product.

a) Addition polymerization is a process in which unsaturated monomers are joined together to form a polymer. The process involves breaking the double bond of the monomer and joining the monomers together to form a long-chain polymer. The process requires a catalyst to initiate the reaction.

b) The repeating unit of the polymer formed from the addition polymerization of chloroethene monomers is -CH2-CHCl-. This polymer is called polyvinyl chloride (PVC), and it has a wide range of uses, including pipes, electrical cables, and vinyl flooring.

The correct response is B. An electron EMITS a photon as it goes from a HIGHER TO LOWER energy level.

A subatomic particle with a negative electric charge is called an electron. Together with protons and neutrons, it is one of the fundamental particles that make up an atom.

When an atom is excited, its electrons have the ability to transition from one energy level to another. These stimulated electrons will eventually revert to their initial lower energy levels since they are unstable. They do this by releasing energy in the form of particular wavelength photons. Each element has a distinct set of energy levels, which leads to the emission of photons at a certain wavelength and the formation of a distinct emission spectrum.

In this instance, the existence of a line in the emission spectrum's blue section shows that an electron has released a photon with a certain wavelength that corresponds to the region's blue color. A photon with an energy equal to the difference between the two levels is released when an excited electron returns from a higher energy level to a lower energy level.

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bababoy jijijijajdiwhrjfofhebdlodvebfif

Answer:

To determine if the solution is saturated or unsaturated, we need to compare the amount of NaCl in the solution to its solubility in water at the given temperature.

The solubility of NaCl in water at room temperature (25°C) is approximately 36 grams per 100 grams of water, or 0.36 g/g. This means that at 25°C, water can dissolve up to 0.36 grams of NaCl per gram of water.

In this case, we have 2.75 grams of NaCl dissolved in 650 grams of water. To find the concentration of NaCl in the solution, we divide the mass of NaCl by the total mass of the solution:

concentration of NaCl = mass of NaCl / total mass of solution

concentration of NaCl = 2.75 g / (2.75 g + 650 g)

concentration of NaCl = 0.0042 g/g

Comparing the concentration of NaCl in the solution to its solubility in water at 25°C, we see that:

0.0042 g/g < 0.36 g/g

Since the concentration of NaCl in the solution is less than its solubility in water, the solution is unsaturated.

Explanation:

Answer: NaAlF6

Explanation:

1) divide by the smallest number of moles

0.953/.322 =2.96 round to 3 Na

.322/.322 = 1 Al

1.93/.322 =5.99 round to 6 F

2) write in order numbers were give

NaAlF6

Answer:

lusterous metal

Explanation:

ex gold, iron etc hope it helps

a balanced equation for the redox reaction: 2 Ca(s) + O2(g) → 2 CaO(s)

A redox reaction is a type of chemical reaction that involves the transfer of electrons between species. One species undergoes oxidation (loses electrons) while another species undergoes reduction (gains electrons).

In the reaction between calcium metal and oxygen gas, the calcium metal is being oxidized (loses electrons) and the oxygen gas is being reduced (gains electrons). This can be seen in the balanced equation where the calcium atoms go from having an oxidation state of 0 to +2, while the oxygen atoms go from having an oxidation state of 0 to -2.

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Answer:

0.8 L

Explanation:

The volume of the stock solution needed to make 2.0 L of 0.20M MgSO4 is 0.8 L.

Answer:

See Below.

Explanation:

Problem 1

Let x be the mass of 15% solution needed and y be the mass of 20% solution needed. Then, we have the following system of equations:

x + y = 200 (total mass of solution)

0.15x + 0.20y = 0.17(200) (total amount of solute)

Solving this system of equations gives:

x = 60 g (mass of 15% solution)

y = 140 g (mass of 20% solution)

Therefore, 60 g of 15% solution and 140 g of 20% solution are needed to prepare 200 g of 17% solution.

Problem 2

Let x be the mass of 18% solution needed and y be the mass of 5% solution needed. Then, we have the following system of equations:

x + y = 300 (total mass of solution)

0.18x + 0.05y = 0.07(300) (total amount of solute)

Solving this system of equations gives:

x = 120 g (mass of 18% solution)

y = 180 g (mass of 5% solution)

Therefore, 120 g of 18% solution and 180 g of 5% solution are needed to prepare 300 g of 7% solution.

Problem 3

The total mass of the final solution is

200 g + 350 g = 550 g

The total amount of solute in the final solution is:

0.15(200 g) + 0.20(350 g) = 95 g + 70 g = 165 g

Therefore, the mass percentage of the final solution is:

(mass of solute / total mass of solution) x 100% = (165 g / 550 g) x 100% = 30%

Therefore, the mass percentage of the final solution is 30%.

Problem 4

The total mass of the final solution is

300 g + 35 g = 335 g

The total amount of solute in the final solution is:

0.15(300 g) + 35 g = 75 g + 35 g = 110 g

Therefore, the mass percentage of the final solution is:

(mass of solute / total mass of solution) x 100% = (110 g / 335 g) x 100% = 32.8%

Therefore, the mass percentage of the final solution is 32.8%.

Problem 5

The total mass of the final solution is

400 g + 150 g = 550 g

The total amount of solute in the final solution is

0.25(400 g) = 100 g

Therefore, the mass percentage of the final solution is

(mass of solute / total mass of solution) x 100% = (100 g / 550 g) x 100% = 18.2%

Therefore, the mass percentage of the final solution is 18.2%.