The polystyrene that was made was a white, semi-transparent solid material.
polystyrene had a smooth texture and was lightweight, yet rigid. It was easily cut and shaped into various forms.The glyptal resin was a slightly yellowish, transparent liquid. It had a thick consistency, similar to that of honey or syrup.The properties of glyptal are quite different from those of polystyrene. Glyptal is much more malleable and can be used to form various shapes and forms. It is also much more heat resistant than polystyrene, and is ideal for use in applications which require the material to withstand high temperatures. On the other hand, polystyrene is much lighter and more rigid, making it ideal for creating objects with precise shapes and dimensions.
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When a diprotic acid is titrated with a strong base, and the Ka1 and Ka2 are significantly different, then the pH vs. volume plot of the titration will have
A. one equivalence point.
B. a pH of 7 at the equivalence point.
C. two distinct equivalence points
D. two equivalence points below 7.
E. no equivalence point
When a diprotic acid is titrated with a strong base, and the Ka1 and Ka2 are significantly different, then the pH vs. volume plot of the titration will have two distinct equivalence points. Thus, the correct answer is option C. For diprotic acids, the two acidic hydrogens (H+) are not lost at the same pH value.
The titration of a diprotic acid with a strong base yields two distinct pH curves as shown in the figure. The plot is also called a two-stage titration graph. The plot is divided into two stages because of the two dissociation steps of the diprotic acid. Titration curve for a diprotic acid. The curve has two equivalence points.
The first equivalence point corresponds to the reaction of the first hydrogen ion (H+) from the diprotic acid with the strong base. The pH at the first equivalence point is generally less than 7 because the salt of the weak acid is an acidic solution.
The second equivalence point occurs when all of the hydrogens have been neutralized. The pH at the second equivalence point is greater than 7 because the salt of the weak acid is a basic solution.
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_ NH3 + __ O2 --> __ NO + __ H2O
Answer:
4NH3 + 5O2 --> 4NO + 6H2O
Explanation:
Balance the elements one at a time to get each value.
Convert the following from moles to number of particles!!SHOW ur WORK
32.45 mol Cr3(PO4)2 = ____ formula units Cr3(PO4)2
6.53 1026 formula units of [tex]\rm Cr_3(PO_4)_2[/tex] are contained in roughly 32.45 moles of [tex]\rm Cr_3(PO_4)_2[/tex].
How to determine atoms?We may use the following procedures to determine how many atoms make up the 32.45 moles of [tex]\rm Cr_3(PO_4)_2[/tex]:
Using Avogadro's number, which is the number of particles (atoms, molecules, or ions) per mole of a substance, we may convert from moles to the number of particles. There are roughly [tex]6.022 \times 10^{23[/tex] particles per mole according to Avogadro's number.
Hence, we can perform the following computation to convert 32.45 moles of [tex]\rm Cr_3(PO_4)_2[/tex] to the quantity of [tex]\rm Cr_3(PO_4)_2[/tex]'s formula units (ions):
32.45 mol [tex]\rm Cr_3(PO_4)_2\times 6.022 \times 10^{23[/tex] formula units/mol = [tex]1.955 \times 10^{25[/tex] formula units [tex]\rm Cr_3(PO_4)_2[/tex]
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potassium chlorate decomposes into potassium chloride and oxygen gas. (True or False)
Answer:
True
Explanation:
(with a manganese dioxide catalyst)
what is the name of an interaction that would form between two ions? group of answer choices hydrogen bonds. none of these (nonpolar molecules do not form imfs). dipole-induced dipole interaction ion-ion interaction ion-dipole interaction ion-induced dipole interaction dipole-dipole interaction
which of the following is true of a thermochemical equation? it includes only the change in enthalpy value. it includes the unbalanced chemical reaction and the change in enthalpy value. it includes the balanced chemical reaction and the change in enthalpy value. it includes only the balanced chemical reaction.
The correct option among the following is (c) it includes the balanced chemical reaction and the change in enthalpy value is true of a thermochemical equation.
A thermochemical equation is a chemical equation that depicts the complete thermochemical reaction. It contains the balanced equation and a written interpretation of the net energy change.
The term "enthalpy of reaction" refers to the heat energy released or absorbed in a chemical reaction at a constant pressure.
Thermochemical equations are written in the same way as chemical equations, with the exception that they also include the change in enthalpy value (ΔH) for the reaction.
The change in enthalpy value reflects the energy absorbed or released by the reaction in the form of heat.
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a compound that converts a mixture of two enantiomers and diastereomers by reacting with them is called a
A compound that can convert a mixture of two enantiomers and diastereomers by reacting with them is called a resolving agent.
Resolving agents are typically chiral compounds that have the ability to selectively interact with one enantiomer or diastereomer in a mixture, leading to the formation of a product that can be separated from the remaining unreacted enantiomer or diastereomer.
Resolving agents can be used in a variety of applications, such as in the synthesis of chiral compounds, the separation of racemic mixtures into their individual enantiomers, and the determination of the absolute configuration of chiral compounds. Common examples of resolving agents include enzymes, chiral metal complexes, and chiral organic molecules such as tartaric acid and its derivatives.
Overall, the use of resolving agents is an important tool in the field of stereochemistry, allowing for the manipulation and separation of chiral compounds in a wide range of applications.
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select each of the following that are true characteristics of phytochemicals. a.substances in plants b.substances found in dairy products c.substances that are essential for life d.substances that may possess health-protective effects
The following are the true characteristics of phytochemicals:
a. substances in plants
d. substances that may possess health-protective effects.
What are Phytochemicals?
Phytochemicals are naturally occurring chemicals found in plant-based foods, such as fruits, vegetables, whole grains, and nuts, that are responsible for their color, taste, and aroma. They are not essential nutrients, but they may help protect against diseases such as cancer, heart disease, and stroke. They are also known as phytonutrients or plant nutrients.
A and D are the correct choices, and they are true characteristics of phytochemicals. B and C are not true about phytochemicals. Hence, option A and option D are the right answer.
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WILL MARK BRAINLIEST PLS HELP! Predict whether or not the following single replacement reaction will happen. If the reaction will occur, write a complete balanced equation.
Bromine + Sodium chloride →
The single replacement reaction between bromine (Br₂) and sodium chloride (NaCl) will occur.
Bromine is a more reactive halogen than chlorine, and it can displace chlorine from its compound. The balanced chemical equation for the reaction is:
Br₂ + 2NaCl → 2NaBr + Cl₂
In this reaction, bromine replaces chlorine to form sodium bromide and chlorine gas. The reaction occurs because bromine is more reactive than chlorine, and it has a higher tendency to gain an electron to form a bromide ion.
Sodium chloride contains positively charged sodium ions and negatively charged chloride ions. When bromine is added to sodium chloride, it reacts with chloride ions to form sodium bromide and chlorine gas. Sodium bromide is an ionic compound that contains positively charged sodium ions and negatively charged bromide ions.
Chlorine gas is a diatomic molecule that contains two chlorine atoms covalently bonded together.
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Silver and sulfur are combined to form 65.0 g silver sulfide. How many atoms of silver are necessary to do this?
3.206 x 10^23 atoms of silver are required to form 65.0 g of silver sulfide.
Steps
To determine how many atoms of silver are necessary to form 65.0 g of silver sulfide, we first need to calculate the number of moles of silver sulfide present in 65.0 g of the compound using its molar mass.
The molar mass of silver sulfide (Ag2S) can be calculated by summing the atomic masses of its constituent atoms:
Molar mass of Ag2S = (2 x atomic mass of Ag) + atomic mass of S
= (2 x 107.87 g/mol) + 32.06 g/mol
= 243.8 g/mol
Now we can calculate the number of moles of Ag2S present in 65.0 g of the compound:
Number of moles of Ag2S = mass of Ag2S / molar mass of Ag2S
= 65.0 g / 243.8 g/mol
= 0.2665 mol
From the chemical formula of silver sulfide (Ag2S), we know that 2 moles of silver are required to form 1 mole of Ag2S. Therefore, we can use this stoichiometric ratio to calculate the number of moles of silver required:
Number of moles of Ag = 2 x number of moles of Ag2S
= 2 x 0.2665 mol
= 0.5330 mol
Finally, we can use Avogadro's number (6.022 x 10^23) to convert the number of moles of silver to the number of atoms of silver:
Number of atoms of Ag = number of moles of Ag x Avogadro's number
= 0.5330 mol x 6.022 x 10^23 atoms/mol
= 3.206 x 10^23 atoms
Therefore, 3.206 x 10^23 atoms of silver are required to form 65.0 g of silver sulfide.
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how much sodium chloride is contained in a fast-food deluxe hamburger that lists a salt content of 2.5 g?
Assuming that all the salt content in the deluxe hamburger is from sodium chloride, then the amount of sodium chloride contained in the hamburger is 2.5 grams.
Salt is composed of sodium chloride (NaCl), and the salt content listed in the deluxe hamburger refers to the amount of NaCl in the hamburger. Therefore, to determine the amount of sodium chloride, we simply use the given salt content value.
Salt content = 2.5 g
Sodium chloride is about 40% sodium by weight (the rest is chloride)
Therefore, the amount of sodium in 2.5 g of sodium chloride is:
2.5 g x 0.40 = 1.0 g
One mole of sodium weighs 22.99 g
Therefore, the number of moles of sodium in 1.0 g is:
1.0 g / 22.99 g/mol = 0.0435 mol
One mole of sodium chloride weighs 58.44 g
Therefore, the number of moles of sodium chloride in 0.0435 mol of sodium is:
0.0435 mol x (1 mol / 1 mol of NaCl) = 0.0435 mol of NaCl
Finally, the mass of sodium chloride in the hamburger is:
0.0435 mol x 58.44 g/mol = 2.54 g
So, there are approximately 2.54 g of sodium chloride in the fast-food deluxe hamburger.
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Why is it important to keep the NaOH solution stoppered at all times when it is not in use? oro To stop the Na OH solution occur the heat reaction with H2CO3, so the Naot solution can keen the best quality when we use it.
It is important to keep NaOH solution stoppered at all times when it is not in use because NaOH is a strong base that readily reacts with carbon dioxide (CO2) in air to form sodium carbonate (Na2CO3).
This reaction is exothermic, meaning that it releases heat, and it can also cause the solution to lose its concentration over time. By keeping the NaOH solution stoppered, exposure to air and carbon dioxide is minimized, which helps to maintain the purity and concentration of solution. In addition, the presence of sodium carbonate can interfere with many chemical reactions, so it is important to minimize its formation in the NaOH solution. Therefore, proper storage of NaOH solution is essential to maintain its quality.
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Which of the following will be more soluble in an acidic solution than in pure water?a. BaSO3b. Zn(OH)2c. CsCIO4d. PbSe. AgCI
The following will be more soluble in an acidic solution than in pure water is e. AgCl.
AgCl (silver chloride) would be more soluble in an acidic solution than in pure water. The solubility of AgCl in water is 0.00013 g/100 mL of water at 25 degrees Celsius, according to the solubility rules. Silver chloride solubility is influenced by the ion concentration in the solution, with higher ion concentrations resulting in greater solubility.
The solubility product constant, Ksp, of AgCl is very low, indicating that it is a sparingly soluble compound. When silver chloride is exposed to light, it decomposes into metallic silver and chlorine. The equation for the reaction is as follows:2 AgCl → 2 Ag + Cl2The other options that were given are not applicable to the given statement.
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how many moles of fe will be formed from 4.1 moles of co? enter only the numeric value for your answer (no units).
The equivalent of 2.05 moles of Fe can be created from 4.1 moles of CO.
The balanced chemical equation for the reaction between CO (carbon monoxide) and Fe₂O₃ (iron(III) oxide) is:
3CO + Fe₂O₃ → 2Fe + 3CO₂
From the equation, we can see that 3 moles of CO reacts with 1 mole of Fe₂O₃ to produce 2 moles of Fe. Therefore, we can set up a proportion:
3 moles of CO / 1 mole of Fe₂O₃ = 2 moles of Fe / 1 mole of Fe₂O₃
Simplifying the proportion, we get:
3 moles of CO = 2 moles of Fe
Now, we can use this proportion to calculate the number of moles of Fe that can be formed from 4.1 moles of CO:
2 moles of Fe = (3 moles of CO / 1 mole of Fe₂O₃) x 4.1 moles of CO
2 moles of Fe = 12.3 moles of CO / mole of Fe₂O₃
Therefore, the number of moles of Fe that can be formed from 4.1 moles of CO is: 2.05 moles of Fe
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D. In many methods that employ multiple measurements, one particular type of measurement may be the "weak link" that limits overall precision. For the density measurements you made here, you will determine what contributes most to the CV of your calculated density - the measurements of mass or of dimensions. Typical standard deviation for length and mass using the equipment employed in this lab are the following:
Dimensions: 0. 01 cm
Mass: 0. 002 g
Select the data for your lightest object, focusing on its mass and its shortest dimension, and answer the following two questions:
(2pts)
What is the CV for the mass value?
(2pts)
What is the CV for the measurement of its shortest dimension?
(2pts)
e. Which type of measurements (mass or dimensions) had the greatest impact on the CV of the measured density? Choose the explanation
Mass measurements have the greater impact because the mass CV with lightest object was greater than its dimension CV.
Mass measurements have the greater impact because the mass CV with lightest object was lesser than its dimension CV.
Dimension measurements have the greater impact because the dimension CV with lightest object was greater than its mass CV.
Dimension measurements have the greater impact because the dimension CV with lightest object was lesser than its mass CV
We can draw the conclusion that compared to dimension measurements, mass readings had a smaller effect on the CV of the measured density.
To determine the contribution of mass and dimensions on the coefficient of variation (CV) of the calculated density, we can calculate the CV for both mass and dimension measurements separately for the lightest object.
Let's assume that the mass of the lightest object is 0.5 g and its shortest dimension is 1.0 cm. The CV for mass can be calculated as follows:
CV for mass = (standard deviation of mass / mean mass) x 100%
CV for mass = (0.002 g / 0.5 g) x 100%
CV for mass = 0.4%
Similarly, the CV for dimension can be calculated as follows:
CV for dimension = (standard deviation of dimension / mean dimension) x 100%
CV for dimension = (0.01 cm / 1.0 cm) x 100%
CV for dimension = 1.0%
From these calculations, we can see that the CV for mass is lower than the CV for dimension, indicating that mass measurements are more precise than dimension measurements for this particular object.
Therefore, we can conclude that mass measurements had a lesser impact on the CV of the measured density compared to dimension measurements. This is because the contribution of mass measurement uncertainty to the overall CV is lower than that of the dimension measurement uncertainty.
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Y’all, I need help on this help me
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maths/ch3m/physics/bio
Consider the dissolution of NaBr and NaI. The values provided here will be helpful for answering the following questions. ΔH∘ soln (kJ/mol) ΔS∘ soln J/mol.K
NaBr –0.860 57.0
NaI –7.50 74.0
Write a balanced equilibrium equation for the dissolution of NaI in water. Include phases?
Which of the following explains why the entropy change is greater for the dissolution of NaI compared to the dissolution of NaBr?
Choose one: A. The interactions between bromide ions with other bromide ions is stronger than the interactions between iodide ions with other iodide ions. B. The cation forms stronger ion-dipole networks with water in NaBr than NaI because of the weaker bond to Br.
C. The more negative change in enthalpy observed with NaI implies greater dissociation and hence greater entropy.
D. Iodide has weaker ion-dipole interactions with water than bromide. E. The bromide ion has a more negative charge than the iodide ion. Therefore, because of the greater charge, it forms a stronger ion-dipole network with water. Calculate the change in free energy if 1.02 moles of NaI is dissolved in water at 25.0°C.
______ kJ What is the dissolution of 1.00 mol of NaBr at 298.15 K?
The balanced equation is NaI → Na⁺ + I⁻, the entropy change is greater for the dissolution of NaI compared to the dissolution of NaBr is iodide has weaker ion-dipole interactions with water than bromide. Option D is correct, the change in free energy is -16.4 kJ/mol, and the dissolution of 1.00 mol of NaBr at 298.15 K is -4.07 kJ/mol.
The Balanced equilibrium equation for the dissolution of NaI in water:
NaI (s) → Na⁺ (aq) + I⁻ (aq)
Iodide having a weaker ion-dipole interactions with water than bromide. This is because the larger size of iodide ion causes weaker electrostatic interactions with water molecules compared to bromide ion. Thus, it requires more disorder or randomness to offset the loss of organization and ordering of water molecules. This results in a higher entropy change for the dissolution of NaI compared to NaBr.
ΔG° = ΔH° - TΔS°
ΔG° = (-7.50 kJ/mol) - (298.15 K)(74.0 J/mol.K)(1.02 mol)
ΔG° = -16.4 kJ/mol
The dissolution of 1.00 mol of NaBr at 298.15 K can be calculated using the following equation:
ΔG° = -RT ln(K)
where R is the gas constant, T is the temperature in Kelvin, and K is the equilibrium constant for the dissolution of NaBr in water.
Since NaBr is a strong electrolyte, it will dissociate completely in water:
NaBr (s) → Na⁺ (aq) + Br- (aq)
The equilibrium constant expression is:
K = [Na⁺][Br⁻]
At equilibrium, the concentration of Na⁺ and Br⁻ will be equal, so:
K = [Na⁺]²
The solubility of NaBr at 298.15 K is 90.7 g/L, which can be converted to mol/L:
90.7 g/L x (1 mol/102.89 g) = 0.881 mol/L
Therefore, [Na+] = [Br-] = 0.881 mol/L, and K = (0.881 mol/L)^2 = 0.775 mol/L.
Plugging in the values:
ΔG° = -8.314 J/mol.K x 298.15 K x ln(0.775 mol/L)
= -4.07 kJ/mol
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in xps the energy of the photoelectron is dependent on the binding energy of the sample. is this also true for an auger electron? explain why or why not.
In X-ray photoelectron spectroscopy (XPS), the energy of the emitted photoelectron is dependent on the binding energy of the sample. However, this is not necessarily true for an Auger electron.
In Auger electron spectroscopy (AES), an atom is ionized by an incident X-ray photon, and the resulting core hole is filled by an outer-shell electron. This process releases energy, which can be detected as an Auger electron. The energy of the Auger electron is dependent on the energy released in the filling of the core hole, rather than the binding energy of the sample.
The energy released in the filling of the core hole depends on the specific electronic configuration of the atom, rather than the binding energy of the sample. Therefore, the energy of an Auger electron is not necessarily dependent on the binding energy of the sample, but rather on the specific electronic transitions that occur during the Auger process.
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For the following question, choose TWO answers. Which question should be asked to determine if the reaction supports the Brønsted-Lowry model of acids and bases?
A
Did an acid donate a hydrogen ion to become a conjugate acid?
B
Did a base accept a hydrogen ion to become a conjugate base?
C
Did an acid donate a hydrogen ion to become a conjugate base?
D
Did a base accept a hydrogen ion to become a conjugate acid?
E
Did an acid donate a hydroxide ion to become a conjugate acid?
F
Did a base accept a hydroxide ion to become a conjugate base?
A and B Did an acid donate a hydrogen ion to become a conjugate acid? Did a base accept a hydrogen ion to become a conjugate base? should be asked to determine if the reaction supports the Brønsted-Lowry model of acids and bases.
In the Bronsted-Lowry hypothesis, proton transport between chemical species is used to characterize acid-base interactions. Any species that can transfer a proton, H, is a Bronsted-Lowry acid and a base is any species that can accept a proton. Based on whether a species receives or donates protons or H+, the Bronstad-Lowry acid-base theory (also known as the Bronsted Lowry theory) distinguishes between strong and weak acids and bases. The hypothesis states that when an acid and base interact, the acid forms its conjugate base and the base forms its conjugate acid by exchanging a proton.
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Which explains the charge of an ion of calcium (Ca)?
A. 2 electrons are gained by the atom.
B. 2 electrons are removed from the atom.
C. 2 protons are removed from the atom.
D. 2 protons are gained by the atom.
Answer:
B. 2 electrons are removed from the atom
Explanation:
The charge of an ion of calcium (Ca) is +2, which means that the calcium atom has lost 2 electrons.
Therefore, the correct answer is B. 2 electrons are removed from the atom.
What is the percent composition of copper in copper (II) sulfate pentahydrate?
Answer: 63.92%
Explanation:
159.62 / 249.72 * 100 = 63.92. This means that a 100-gram sample of copper sulfate pentahydrate will contain 63.92 grams of copper sulfate. I hope this helps!
it is usually the case that heating a solution containing an enzyme markedly decreases the enzyme's activity. what might be the reason for this? the ability of a substrate to bind to its enzyme will decrease as temperature increases. increasing the temperature of a reaction will decrease the available free energy due to the increased entropy of the reaction. the elevated temperature will increase the activation energy of the catalyzed reaction. heating the solution will denature the enzyme.
Heating a solution containing an enzyme usually decreases the enzyme's activity. The reason for this might be: heating the solution will denature the enzyme. The correct option is D.
This may be due to the fact that: heating increases the enzyme's temperature, which may have a variety of effects on the reaction. Enzyme reactions are catalyzed by proteins, which are sensitive to temperature changes. Temperature can cause the enzyme to denature, which causes a structural change in the protein, resulting in a loss of function.
The enzyme's substrate ability to bind will decline as the temperature rises. As a result, raising the temperature of the reaction will reduce the amount of available free energy due to the increased entropy of the reaction. The elevated temperature may also raise the activation energy of the catalyzed reaction.
Enzyme activity is influenced by the temperature and pH of the environment in which they are located. It is important to keep the enzymes at the appropriate temperature and pH level to avoid denaturation and maintain enzyme activity. Enzyme function can be adversely affected by environmental factors such as temperature, pH, and salt concentration.
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Complete Question:
It is usually the case that heating a solution containing an enzyme markedly decreases the enzyme's activity. What might be the reason for this?
a. The ability of a substrate to bind to its enzyme will decrease as temperature increases.
b. Increasing the temperature of a reaction will decrease the available free energy due to the increased entropy of the reaction.
c. The elevated temperature will increase the activation energy of the catalyzed reaction.
d. Heating the solution will denature the enzyme.
an unknown compound exhibits a signal at 170 ppm in its 13c nmr spectrum. treatment with two equivalents of lialh4 followed by aqueous workup gives an amine. what could be the identity of the unknown compound?
The existence of a carbonyl group in the unidentified chemical is indicated by the signal at 170 ppm in the 13C NMR spectra.
What number of peaks or signals would you anticipate to see in the ethyl acetate C-13 NMR spectrum?It displays the four anticipated signals one for each of the carbonsas expected.
How many peaks does a carbon atom in a chemical cause the 13C NMR spectrum to produce?Four carbons and four peaks are present. No two carbons exist in the same environment exactly. The peak at slightly over 50 must be a carbon with a single bond connecting it to an oxygen.
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If the specific heat of the solid is 1.56J/gC, the specific heat for the liquid is 3.11 J/gC, the specific heat of the gas is .988 J/gC, the heat of fusion is 107 J/g, and the heat of vaporization is 854 J/g, Calculate all the energy absorbed by the sample as described above.
The total energy absorbed by the sample is 34276m + 30075.2 J.
What is the heat of fusion?The heat of fusion is the amount of heat required to melt one unit of mass of a substance at its melting point without a change in temperature.
What is the heat of vaporization?The heat of vaporization is the amount of heat required to vaporize one unit of mass of a substance at its boiling point without a change in temperature.
To calculate the energy absorbed by the sample, we need to know the mass of the sample and the temperature changes it undergoes. Assuming the sample starts as a solid at a temperature of -20°C, is heated to its melting point, melted, then heated to its boiling point, and finally vaporized, the calculations are as follows:
Energy absorbed to heat the sample from -20°C to 0°C:
Q = m * C * ΔT
Q = m * 1.56 J/g°C * (0°C - (-20°C))
Q = 31.2 * m J
Energy absorbed to melt the sample at 0°C:
Q = m * Hfus
Q = 107 J/g * 31.2 g
Q = 3338.4 J
Energy absorbed to heat the sample from 0°C to 100°C:
Q = m * C * ΔT
Q = m * 3.11 J/g°C * (100°C - 0°C)
Q = 311 * m J
Energy absorbed to vaporize the sample at 100°C:
Q = m * Hvap
Q = 854 J/g * 31.2 g
Q = 26636.8 J
Energy absorbed to heat the sample from 100°C to 200°C:
Q = m * C * ΔT
Q = m * 0.988 J/g°C * (200°C - 100°C)
Q = 98.8 * m J
Total energy absorbed:
Qtotal = 31.2m + 3338.4 + 311m + 26636.8 + 98.8m
Qtotal = 34276m + 30075.2 J
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45. a 250.0-ml buffer solution is 0.250 m in acetic acid and 0.250 m in sodium acetate. what is the initial ph of this solution? what is the ph after addition of 0.0050 mol of hcl? what is the ph after addition of 0.0050 mol of naoh?
The initial pH of the buffer solution is 4.76, the pH after the addition of 0.0050 mol of HCl is 4.63, and the pH after the addition of 0.0050 mol of NaOH is 4.89.
What is buffer solution?A buffer solution contains a weak acid and its corresponding salt, or a weak base and its corresponding salt. A buffer solution maintains a stable pH when an acid or a base is added to it. The following are the steps to solve the given problem.
The initial pH of a buffer solution can be calculated by the Henderson-Hasselbalch equation.
pH = pKa + log [A-]/[HA]pKa of acetic acid is 4.76A- = concentration of acetate ion = 0.250 mM HA = concentration of acetic acid = 0.250 mm pH = 4.76 + log [0.250]/[0.250]pH = 4.76The addition of HCl will consume the acetate ions and increase the concentration of H+. The new buffer concentration will have a lesser concentration of acetate ion than the acetic acid, and the pH will decrease. Let x be the change in concentration of acetate ion, and 0.0050 - x be the new concentration of acetate ion.
The concentration of acetic acid is 0.250 M. After calculating x, the new pH can be calculated.
pH = pKa + log [A-]/[HA]x = 0.0050 mol/L of acetate ion consumed.
The concentration of the remaining acetate ion
= 0.250 - x0.250 - x = 0.2450 mol/L of acetate ion remaining [H+] = 0.0050 mol/L HCl added.
initial pH = 4.76
New pH = pKa + log [A-]/[HA] = 4.76 + log [0.2450]/[0.250] + log [0.0050]/[0.2450]
New pH = 4.63
The addition of NaOH will consume H+ ions and generate acetate ions. The new buffer concentration will have a greater concentration of acetate ion than the acetic acid, and the pH will increase.
Let y be the change in concentration of H+ ion, and 0.0050-y be the new concentration of H+ ion. The concentration of acetate ion is 0.250 M. After calculating y, the new pH can be calculated.
pH = pKa + log [A-]/[HA]y = 0.0050 mol/L of H+ ion consumed.
The concentration of the remaining H+ ion = 0.0050 - y0.250 + y = 0.2550 mol/L of acetate ion remaining[OH-] = 0.0050 mol/L NaOH added
initial pH = 4.76
New pH = pKa + log [A-]/[HA] = 4.76 + log [0.2550]/[0.250] - log [0.0050]/[0.2550]
New pH = 4.89
Therefore, the initial pH of the buffer solution is 4.76, the pH after the addition of 0.0050 mol of HCl is 4.63, and the pH after the addition of 0.0050 mol of NaOH is 4.89.
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what two gases are the primary causes of acid deposition
The two gases that are the essential drivers of acid deposition are sulfur dioxide (SO2) and nitrogen oxides (NOx).
These gases collaborate in the atmosphere to frame fine sulfate and nitrate particles that can be transported significant distances by winds and breathed profoundly into individuals' lungs.
Some sources of sulfur dioxide incorporate the consumption of fossil fuels such as coal, oil, and natural gas, petrol refineries, concrete assembling, paper mash production, metal smelting and processing facilities, and volcanic eruptions.
Sulfur dioxide can irritate the nose, throat, and airways causing hacking, wheezing, shortness of breath, or a tight searching of the chest. High concentrations of SO2 can cause inflammation and irritation of the respiratory system. Individuals with lung diseases such as asthma, constant bronchitis, and emphysema are for the most part more sensitive to sulfur dioxide. Youngsters are at higher risk from SO2 exposure because their lungs are still creating. Exposure to sulfur dioxide might irritate the eyes, nose, and throat.
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Determine the mass of one atom of gold,Au.(molar mass of Au:196.97)g
1 atom Au multiplied by 196.96655g/mol x 1mol/6.022 x 1023 atoms equals 3 x 10-22g Au
An element's molar mass equals its atomic weight. In the instance of gold, Au, the molecular mass per mole is 196.967 grams.
Au molar mass = 196.96655 g/mol Convert ounces au to moles or moles to au gold to grams Composition percentage by ingredient Determine an organic compound's molecular weight.
As per the given details, the mass of one atom of gold (Au) is approximately 3.27 x [tex]10^_{-22[/tex] grams.
We may use the molar mass of gold and Avogadro's number to calculate the mass of one gold atom (Au). The particle density of Avogadro's number, abbreviated "NA," is roughly 6.022 x [tex]10^{23[/tex] particles per mole.
It is given that,
Molar mass of gold (Au) = 196.97 g/mol
Mass of one atom of gold = (Molar mass of gold) / (Avogadro's number)
Mass of one atom of gold = (196.97 g/mol) / (6.022 x [tex]10^{23[/tex] particles/mol)
Mass of one atom of gold ≈ 3.27 x [tex]10^_{-22[/tex] grams
Thus, the molar mass is 3.27 x [tex]10^_{-22[/tex] grams.
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in bromination what is the intermediate step
In the bromination process, the intermediate step is the formation of a bromonium ion.
What is bromination?Bromination is the process of introducing bromine into a molecule. When an alkene is reacted with bromine, the alkene will undergo electrophilic addition. The addition of bromine to an alkene is an example of an electrophilic addition reaction. This is because the bromine molecule acts as the electrophile during the reaction. The electrophilic addition process can be broken down into three steps:
Step 1: The pi electrons in the alkene are attracted to the partially positive bromine.
Step 2: The pi electrons from the alkene form a bond with one of the bromine atoms.
Step 3: The bromine-bromine bond is broken and a bromine atom attaches to each of the carbon atoms.
What is the intermediate step in bromination?The formation of a bromonium ion is the intermediate step in the bromination process. The bromonium ion is a three-membered ring that contains a positively charged bromine atom. The bromonium ion is formed because the bromine molecule is not polarized enough to react directly with the pi electrons in the alkene. Instead, the bromine molecule is polarized by a solvent, such as water or acetic acid.
The polarized bromine molecule then acts as an electrophile and reacts with the alkene to form a bromonium ion. The bromonium ion is highly reactive and will react with a nucleophile, such as water or bromide ion, to form a vicinal dihalide.
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molarity how can the concentration of a solution be expressed quantitatively?
The concentration of a solution can be expressed quantitatively through the concept of molarity.
What is Molarity?The number of moles of solute present in one liter of the solution is called molarity (M). It is a quantitative measure of the concentration of a solution. The following formula is used to calculate the molarity of a solution:
Molarity = Moles of solute/Liters of solutionIn other words, molarity is a measure of how many moles of solute are dissolved in one liter of the solution. It is generally expressed in moles per liter (mol/L). For example, a 0.1 M solution of sodium chloride means that there are 0.1 moles of sodium chloride present in one liter of the solution.
Importance of MolarityMolarity is an important concept in chemistry as it is used to determine the amount of a chemical substance in a solution. It is widely used in chemical reactions, stoichiometry, and in the calculation of pH, equilibrium constants, and other important chemical properties. It is also a useful measure in analytical chemistry and in the preparation of reagents for scientific experiments. Molarity plays a significant role in many areas of chemistry, including biochemistry, medicinal chemistry, and environmental chemistry.
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What are the names of the two common regenerated fibers?
The two common regenerated fibers are viscose rayon and lyocell. Both viscose rayon and lyocell have similar properties to natural fibers such as cotton and silk, but with the added benefit of being more affordable and easier to produce in large quantities.
Viscose rayon is a regenerated cellulose fiber made from wood pulp or cotton linters, and it has been used in the textile industry since the early 1900s. The manufacturing process involves dissolving the wood pulp or cotton linters in a chemical solution to form a viscous solution, which is then extruded through a spinneret and solidified into fibers.
Lyocell, also known as Tencel, is a newer type of regenerated cellulose fiber made from wood pulp, usually from eucalyptus trees. The manufacturing process for lyocell is more environmentally friendly than that of viscose rayon, as it uses a closed-loop process that recycles the solvent used in the production process. The resulting fibers are strong, durable, and moisture-absorbent, making them popular for use in clothing and textiles.
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