How Scandium affects the government
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The standard change in Gibbs energy at 25 degree Celsius is 490.6 °C. for given equilibrium partial pressure .
What is Gibbs energy ?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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FILL IN THE BLANK. Use the Gizmo to find the freezing, melting, and boiling points of water at 5,000 meters (16,404 feet). Write these values below. Freezing point: _______ Melting point: _______ Boiling point: _______
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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Which of the following is the major organic product of the condensation of ammonia or a primary amine with the carbonyl group of an aldehyde or ketone?
Imine
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?
!!!50 points!!!
Problem 1. What masses of 15% and 20% solutions are needed to prepare 200 g of 17% solution?
Problem 2. What masses of 18% and 5% solutions are needed to prepare 300 g of 7% solution?
Problem 3. 200 g of 15% and 350 g of 20% solutions were mixed. Calculate mass percentage of final solution.
Problem 4. 300 g of 15% solution and 35 g of solute were mixed. Calculate mass percentage of final solution.
Problem 5. 400 g of 25% solution and 150 g of water were mixed. Calculate mass percentage of final solution.
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%.
Carbenes can add to alkenes to give a cyclopropane deriverative. Draw the alkene (unknown X) that reacts with the carbene to give the following product. Be sure to clearly indicate the stereochemistry of the alkene by drawing all bonds at the sp2 carbons.
The product of the addition of the carbene to the unknown alkene X is a cyclopropane derivative, with the same stereochemistry as the alkene X.
Carbenes are molecules containing a carbon atom with two non-bonding electrons and a triple bond, and can add to alkenes to give a cyclopropane derivative. The alkene (unknown X) that reacts with the carbene to give the following product is shown in the following diagram. Note that the two sp2 carbons on either side of the double bond are stereochemically distinct, with one carbon pointed "up" and the other pointed "down".
When the carbene adds to the double bond, a three-membered ring forms. This three-membered ring adopts a chair conformation, and the alkene stereochemistry is maintained in the product.
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which one of the following elements will combine with chlorine in a 1:2 ratio to give a formula of xcl 2 ? f al c mg na
Answer: the answer is Mg
Explanation: Trust me
You submerge 100 grams of steel in 200 grams of water. If the steel has an initial temperature of 90°C and the water has an initial temperature of 15°C, what is the final temperature of the system? The specific heat capacity of the steel is 0.15 cal/g °C.
the final temperature of the system is 7.3°C.
1) what is the empirical formula of a molecule containing 65.5% carbon, 5.5% hydrogen, and 29% oxygen? worksheet
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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2. Hydrogen bromide reacts with propene to form either 1-bromopropane or 2-bromopropane. Explain why
2-bromopropane is the major product.
3. Explain how the reaction with bromine can be used to test for an alkene. Include the mechanism for the reaction between hex-1-ene and bromine in your answer.
a) Describe the process of addition polymerisation.
b) Show the repeating unit of the polymer that is formed from the addition polymerisation of chloroethene monomers. Name and give at least one use for this polymer.
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.
There are 7.68 × 1025 atoms of phosphorous in how many moles of diphosphorous pentoxide?
Answer:
7.68 x 1025 atoms of phosphorous correspond to 1.06 mole of diphosphorous pentoxide. This can also be written as 1.06 mol of P2O5.
Which equation is a correctly written thermochemical equation?
OC3H8 (g) +502 (g) → 3CO2 (g) + 4H₂O (1), AH= -2,220 kJ/mol
OFe (s) + O2 (g) → Fe₂O3 (s), AH= -3,926 kJ
ONH₂Cl → NH₂ + + Cl
O2C8H18 + 250216CO2 + 18H₂O, AH=-5,471 kJ/mol
Answer:
The correctly written thermochemical equation is:
C3H8 (g) + 5O2 (g) → 3CO2 (g) + 4H2O (l), ΔH = -2,220 kJ/mol
This equation represents the combustion of propane (C3H8) in the presence of oxygen (O2) to produce carbon dioxide (CO2) and water (H2O), with a heat release of -2,220 kJ/mol. The state symbols (g) for gases and (l) for liquids indicate the physical state of each substance at standard conditions.
Explanation:
ABOVE
______ is produced anytime current flows in a circuit, due to the collision between the flowing free electrons and the fixed atoms.
Heat is produced anytime current flows in a circuit, due to the collision between the flowing free electrons and the fixed atoms. When an electric current flows through a conductor, the free electrons move through the lattice of atoms.
As they move, they collide with the fixed atoms, causing the atoms to vibrate and transfer energy to neighboring atoms. This energy transfer increases the temperature of the conductor, resulting in the production of heat.
The amount of heat produced is directly proportional to the amount of current flowing through the conductor, the resistance of the conductor, and the time for which the current flows. This relationship is described by Joule's law, which states that the heat produced is equal to the product of the current, the resistance, and the time.
Mathematically, this can be expressed as H = I^2RT, where H is the heat produced, I is the current, R is the resistance, and T is the time. The collision between the flowing free electrons and the fixed atoms in a conductor leads to the production of heat, which is proportional to the current, resistance, and time for which the current flows.
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According to Table F, which substance is least soluble?
NaNO3
BaSO4
KCl
KSO4
which of the following statements may be true regarding a biochemical oxidation-reduction (redox) reaction?
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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Chemistry Help Please! It's worth a lot of points
1.Write the equilibrium expression for the following reactions
a. H2SO4(aq) + H2O(L) ⇆ HSO4-(aq) + H3O+(aq)
b. 4NH3(g) + 5O2(g) ⇆ 4NO(g) + 6H2O(g)
c. NH4Cl(s) ⇆ NH3(g) + HCl(g)
d. N2O4(g) ⇆ 2NO2(g)
2. The following reaction has a K value of 0.050. What does that mean about the concentrations of the reactants as compared to the products? Be specific in your answer.
N2(g) + 3H2(g) ⇆ 2NH3(g)
3. The following reaction has a K value of 6.8 x 103. What does that mean about the concentrations of the reactants as compared to the products? Be specific in your answer.
2SO3(g) ⇆ 2SO2(g) + O2(g)
4. When dissolving substances in water, the degree of solubility of a substance is often represented as the solubility product constant (Ksp). The solubility product constant is the same thing as the equilibrium constant for the dissolving reaction. Two substances that dissociate in water are shown below alone with the Ksp.
NaCl(s) ⇆ Na+(aq) + Cl-(aq) Ksp = 36
BaSO4(s) ⇆ Ba2+(aq) + SO42-(aq) Ksp = 1.1 x 10-16
5. Identify and label the Brønsted-Lowry acid, its conjugate base, the Brønsted-Lowry base, and its conjugate acid in each of the following equations:
a. HNO3 + H2O ⟶ H3O+ + NO3−
b. CN− + H2O ⟶ HCN + OH−
c. H2SO4 + Cl− ⟶ HCl + HSO4−
d. HSO4− + OH− ⟶ SO42− + H2O
e. O2− + H2O ⟶2OH−
6. What is the conjugate acid of each of the following? What is the conjugate base of each of the following?
a. OH-
b. H2O
c. HCO3-
d. NH3
e. HSO4-
7. The following acids are shown with their equilibrium constants (also known as the acid dissociation constant). Rank these acids from strongest to weakest. Explain your ranking.
HCN(aq) + H2O(L) ⇆ H3O+(aq) + CN-(aq) K = 6.2 x 10-10
HC2H3O2(aq) + H2O(L) ⇆ H3O+(aq) + C2H3O-(aq) K = 1.75 x 10-5
H2CO3(aq) + H2O(L) ⇆ H3O+(aq) + HCO3-(aq) K = 4.5 x 10-7
HIO4(aq) + H2O(L) ⇆ H3O+(aq) + IO4-(aq) K = 2.3 x 10-2
8. Calculate the pH and the pOH of each of the following solutions.
a. 0.200 M HCl
b. 0.0143 M NaOH
c. 3.0 M HNO3
d. 0.0031 M Ca(OH)2
9. Wine has a pH of 3.6. What are the hydronium and hydroxide ion concentrations?
10. The hydroxide ion concentration in household ammonia is 3.2 x 10-3 M. What is the concentration of hydronium ions?
Answer:
1. Equilibrium expressions:
a. K = [HSO4-][H3O+]/[H2SO4][H2O]
b. K = [NO]^4[H2O]^6/[NH3]^4[O2]^5
c. K = [NH3][HCl]/[NH4Cl]
d. K = [NO2]^2/[N2O4]
2. Since K = 0.050, the concentrations of the reactants (N2 and H2) are larger than the concentrations of the products (NH3).
3. Since K = 6.8 x 10^3, the concentrations of the products (SO2 and O2) are larger than the concentrations of the reactant (SO3).
4. The Ksp expression for each of the reactions is:
a. Ksp = [Na+][Cl-]
b. Ksp = [Ba2+][SO42-]
5. Brønsted-Lowry acids and bases:
a. Acid: HNO3; Conjugate base: NO3-; Base: H2O; Conjugate acid: H3O+
b. Acid: HCN; Conjugate base: CN-; Base: H2O; Conjugate acid: HCN
c. Acid: H2SO4; Conjugate base: HSO4-; Base: Cl-; Conjugate acid: HCl
d. Acid: NH3; Conjugate base: NH2-; Base: H2O; Conjugate acid: NH4+
e. Acid: H2O; Conjugate base: OH-; Base: O2-; Conjugate acid: OH-
6. Conjugate acids and bases:
a. Acid: H2O; Conjugate base: OH-
b. Acid: H3O+; Conjugate base: H2O
c. Acid: H2CO3; Conjugate base: HCO3-
d. Acid: NH4+; Conjugate base: NH3
e. Acid: HSO4-; Conjugate base: SO42-
7. The strongest acid is HIO4 (highest K value), followed by HCN, HC2H3O2, and H2CO3 (lowest K value). The K values represent the degree to which the acids dissociate in solution. HIO4 is a strong acid, meaning it dissociates almost completely in solution, while H2CO3 is a weak acid, meaning it only dissociates partially.
8. pH and pOH calculations:
a. pH = -log[H3O+] = -log(0.200) = 0.699; pOH = -log[OH-] = -log(1.0 x 10^-14/0.200) = 12.301
b. pOH = -log[OH-] = -log(0.0143) = 1.844; pH = 14.000 - pOH = 12.156
c. pH = -log[H3O+] = -log(3.0) = 0.522; pOH = 13.478
d. pOH = -log[OH-] = -log(0.0062) = 2.206; pH = 14.000 - pOH = 11.794
9. Hydronium and hydroxide ion concentrations:
pH = 3.6; hydronium ion concentration = 10^-pH = 3.98 x 10^-4 M; hydro
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Using the formula M1V1 = M2V2 , you have a 0.5 M MgSO4 stock solution available. Calculate the volume of the stock solution needed to make 2.0 L of 0.20M MgSO4.
Question 2 options:
4.0 L
0.9 L
0.8 L
0.5 L
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.
4. An aqueous solution contains NaNO and KBr The bromide ion is precipitated as AgBr by addition of AgNO. After an excess of the precipitating reagent has been added, a. what is the charge on the surface of the coagulated colloidal particles? b. what is the source of the charge? c. what ions make up the counter-ion layer?
The charge on the surface of the coagulated colloidal particles is negative.
The source of the charge is likely due to the dissociation of the sodium and potassium salts in water, which results in the formation of ions.
The counter-ion layer is composed of the cations that balance the charge on the negatively charged colloidal particles.
What is a Charge?Charge is a fundamental property of matter that describes the amount of electrical energy present in a particle, atom, or molecule. It is a property that can be either positive or negative and is measured in units of coulombs (C).
The charge of a particle can affect how it interacts with other charged particles. For example, particles with opposite charges are attracted to each other, while particles with the same charge repel each other. The interaction between charged particles is fundamental to many chemical and physical phenomena, such as electrostatic interactions, chemical bonding, and the behavior of electrical currents.
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What is the pH of 0.335 M trimethylammonium chloride, (CH3)3NHCI? The Kb of trimethylamine, (CH3)3N, is 6.3 x 10-5. (value = 0.02)
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.
consider this segment of polypeptide compound found in wasp venom. identify the amide bonds in this compound.
The polypeptide compound found in wasp venom have the amide bonds known as peptide bond between O and NH.
What are polypeptides?A polypeptide is a continuous, unbranched chain of amino acids linked by peptide bonds. To create an amide, a peptide bond connects the carboxyl group of one amino acid to the amine group of the next amino acid. Proteins play an important role in biology, serving as the building blocks of muscles, bones, hair and nails, building enzymes, antibodies, muscles, connective tissue, and much more. Peptides are shorter chains of amino acids. They differ from polypeptides in that they are composed.
When 10 or more α-amino acids are linked by peptide bonds (-CONH-), the resulting polyamide is called a polypeptide. This bond is formed by a condensation reaction between the carboxylic acid group of one amino acid and the amine group of another, resulting in the desired amide bond and the loss of a water molecule.
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how many moles of CaO will form if 10.0 moles of CO2 are produced
A 106 mL solution of a dilute acid is added to 157 mL of a base solution in a coffee-cup calorimeter. The temperature of the solution increases from 22.94 oC to 27.29 oC. Assuming the mixture has the same specific heat (4.184J/goC) and density (1.00 g/cm3) as water, calculate the heat (in J) transferred to the surroundings, qsurr.
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.
How many calories are required to raise the temperature of a 35.0 g sample from 35 °C to 85 °C? The sample has a specific heat of 0.108 cal/g °C.
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
Determine the empirical formula for a compound that is composed of 0.953 mol Na, 0.322 mol Al, and 1.93 mol F.
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
write a balanced equation for the redox reaction between calcium metal and oxygen gas
a balanced equation for the redox reaction: 2 Ca(s) + O2(g) → 2 CaO(s)
What is a redox reaction?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).
Which species is being oxidized and which species is being reduced in the reaction between calcium metal and oxygen gas?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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Menthol is composed of C, H, and O. A 0.1005g sample of menthol is combusted, producing 0.2829g of CO2 and 0.1159g H2O. What is the empirical and molecular formula for menthol?
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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Some metalloids are liquids at room temperature.
TRUE
FALSE
Answer:
Some metalloids are liquids at room temperature.
FALSEThey are all solid at room temperature.
Explanation:
You're welcome.
metals that have luster are usually called as______
Answer:
lusterous metal
Explanation:
ex gold, iron etc hope it helps
How many moles are 2.96 x 1020 atoms of iron?
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
Consider the following silica gel TLC plate of compounds A, B, and C developed in hexanes:
Consider the following silica gel TLC plate of com
a) Determine the R f values of compounds A, B, and C run on a silica gel TLC plate using hexanes as the solvent
b) Which compound, A, B, or C, is the most polar?
c) What would you expect to happen to the R f values if you used acetone instead of hexanes as the eluting solvent? (Think polarity of solvents)
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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