The process of standardization involves calculating the precise concentration (molarity) of a solution. One type of analytical process that is frequently employed in standardization is titration. A precise volume of one chemical is reacted with a known quantity of another substance in a titration.
The endpoint of a titration is the point at which the reaction is finished. The endpoint is indicated (signaled) using an indicator chemical substance. Phenolphthalein is the indicator utilized in this experiment. Organic compound phenolphthalein is colorless in acidic solution and pink in basic solution.
In this standardization, a sample of potassium acid phthalate (KHP; HKC8H4O4) will be titrated with a sodium hydroxide solution (NaOH) to measure the molarity of the NaOH.
HKC8H4O4 + NaOH -----> NaKC8H4O4 + H2O
(1.502 g KHP)(1 mol / 204.23 g KHP ) = 6.267 x 10-4 mol KHP
(6.267 x 10-4 mol KHP)(1 mol NaOH / 1 mol KHP) = 6.267 x 10-4 mol NaOH
6.267 x 10-4 mol NaOH / 0.02854 L NaOH = 0.0220 M NaOH
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Example: The products of a chemical reaction are Sodium Hydroxide and Acetone.
Without knowing the reactants, how do you know that this is not a synthesis reaction?
The products of the chemical reaction are sodium hydroxide and acetone. This is because acetone undergoes aldol condensation. Synthetic reactions occur when two or more reactants combine to form a single product.
Sodium hydroxide is completely ionic and contains sodium and hydroxide ions. The hydroxide ion makes sodium hydroxide a strong base and reacts with acids to form the corresponding salts with water. The chemical formula for acetone is CH32CO. Also known as propanone or dimethyl ketone, it is the smallest and simplest ketone. It forms an iodoform when it reacts with iodine in the presence of NaOH. Thus it can be seen that iodoform is formed in the presence of NaOH.
Hydrochloric acid and caustic soda interact to form salts and release heat. As you can see table salt and water are the results of the interaction of two highly aggressive compounds. These compounds are ultimately harmless and even beneficial to humans. The reaction between benzaldehyde and acetophenone undergoes cross-aldol condensation in the presence of di-I. Sodium hydroxide. In this reaction, benzaldehyde has no alpha hydrogen.
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When mass is "destroyed", what is released?
Mass can neither be created nor destroyed.
What is mass?Mass is described as the quantity of matter in a physical body. It can also be a measure of the body's inertia, the resistance to acceleration when a net force is applied.
The law of conservation of mass helps us to understand that mass can neither be created nor destroyed, although it may be rearranged in space, or the entities associated with it may be changed in form.
According to the law of conservation of mass, the mass of the reactants must be equal to the mass of the products for a low energy thermodynamic process.
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using periodic table write full electron configuration of bromine so that all subshells in each principle energy cell are grouped together
The atomic number 35 and symbol Br identify the chemical element bromine. The third-lightest halogen, it is a volatile reddish-brown liquid that easily evaporates to produce a vapour of a similar color. Its characteristics fall in between iodine and chlorine.
Bromine's electron configuration is [Br]4s^2.3d^10.4p^5
A maximum of two electrons can fit into a s subshell, six into a p subshell, ten into a d subshell, and fourteen into a f subshell.
The maximum number of electrons in a subshell and the number of orbitals may both be calculated using the angular momentum quantum number, l, which stands for various subshells. These quantities can be found using the formulas 2 ( 2 l + 1 ) and 2 l + 1 correspondingly.
The s subshell is represented by a l of 0, the p subshell by a l of 1, the d subshell by a l of 2, and the f subshell by a l of 3.
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you gently shake an amine, a carboxylic acid, and a phenol in a separatory funnel with ethyl acetate and aq naoh. which one of the following will be true?
The amine will remain in the upper organic (ethyl acetate) layer, while the phenol and the carboxylic acid will be in the lower aqueous layer. Effectively, a separation of amine will be achieved using basic extraction technique.
Sodium hydroxide (NaOH) makes a basic solution when dissolved in water. It will react with the acidic components of the analyzed mixture during extraction. Amine is also basic, so it will not interact with sodium hydroxide and will remain in the organic layer. Carboxylic acid is, as the name implies, acidic, and thus will be neutralized by sodium hydroxide, forming a water-soluble sodium carboxylate salt, which means that it will be removed from the organic layer. Phenol is also acidic enough to be neutralized by sodium hydroxide, so it will also form a water-soluble salt (sodium phenoxide) and be removed from the organic layer.
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How might the world be different if all gases behaved ideally?
(Use photo to answer)
Gases are most ideal at high temperature and low pressure.
What are the differences between real and ideal gases when are the real gases most like ideal gases?Gases that are ideal and real. An perfect gas is also referred to as a point mass since its particles are so small, it has nearly no mass, and it has no volume.A theoretical gas known as an ideal gas is made up of several randomly moving particles without interparticle interactions. The converse is true for a genuine gas; its molecules interact and it takes up space. Due to this, PV is always equal to nRT.Because it links the amount of a gas (in terms of moles) to its pressure, volume, and temperature, the ideal gas law is the last and most usable statement of the gas laws. In chemical and engineering calculations involving gases, the ideal gas law is a vital tool.To learn more about : Ideal gas law
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a 1.631 g sample of an unknown triprotic acid was dissolved in water and diluted to 250.0 ml in a volumetric flask. 20.00 ml of the acid solution required 19.74 ml of 0.1063 m naoh to reach the endpoint of the titration. determine the molar mass of the triprotic acid
The molar mass of the triprotic acid used is 186.4 g/mol.
To calculate the amount of triprotic acid, we must first calculate the number of moles (n) of sodium hydroxide (NaOH) expended during the titration. To do this, we can use its molarity (c = 0.1063 M) and volume (V = 19.74 mL = 0.01974 L):
c = n/V ⇒ n = c*V
n(NaOH) = 0.1063 M * 0.01974 L
n(NaOH) = 0.0021 mol
Because 1 mol of a triprotic acid requires 3 moles of sodium hydroxide to be neutralized, the amount of the acid in the 20.00 mL sample will be:
n(acid) = n(NaOH) / 3
n(acid) = 0.0021 mol / 3
n(acid) = 0.0007 mol
Now we use a proportion to calculate the amount of acid present in a 250.0 mL sample:
0.0007 mol : 20.00 mL = X : 250 mL
X = 0.0007 mol * 250.0 mL / 20.00 mL
X = 0.00875 mol
Finally, we use the mass (m) and the number of moles to calculate the molar mass (M):
n = m/M ⇒ M = m/n
M = 1.631 g / 0.00875 mol
M = 186.4 g/mol
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Which of these is an example of a physical change?
Responses
baking bread
baking bread
digesting bread
digesting bread
toasting bread
toasting bread
breaking bread
Answer:
Breaking the bread
Explanation:
Because you're just breaking the bread into pieces.
how do you balance a element year9 chemistry ?
Answer:
Balancing a chemical equation involves a certain amount of trial and error. In general, however, you should follow these steps:
Count each type of atom in reactants and products. Does the same number of each atom appear on both sides of the arrow? If not, the equation is not balanced, and you need to go to step 2.
Place coefficients, as needed, in front of the symbols or formulas to increase the number of atoms or molecules of the substances. Use the smallest coefficients possible. Warning! Never change the subscripts in chemical formulas. Changing subscripts changes the substances involved in the reaction. Change only the coefficients.
Repeat steps 1 and 2 until the equation is balanced.
Explanation:
Light of frequency 9.62 x 1014 Hz
(312 nm) strikes a surface of calcium
(Wo = 2.90 eV). How much kinetic
energy does the liberated electron
have in Joules?
The kinetic energy of the liberated electron is 1.73 x 10⁻¹⁹ J.
What is the energy of the light?
The total energy of the light is the sum of the kinetic energy of the electron and work function of the metal.
E = K.E + Ф
where;
K.E is the kinetic energy of the liberated electronФ is the work function of the metalThe total energy of the photons of light is calculated as follows;
E = hf
where;
f is the frequency of the lighth is Planck's constantE = (6.626 x 10⁻³⁴) x (9.62 x 10¹⁴)
E = 6.37 x 10⁻¹⁹ J
1 eV = 1.6 x 10⁻¹⁹ J
E = 6.37 x 10⁻¹⁹ J = 3.98 eV
The kinetic energy of the liberated electron is calculated as;
E = K.E + Ф
K.E = E - Ф
K.E = 3.98 eV - 2.9 eV
K.E = 1.08 eV = 1.73 x 10⁻¹⁹ J
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pure benzene freezes at 5.53°c and boils at 80.10 oc. a solution of a certain solute in benzene freezes at 1.00 oc. what is the boiling point of this solution? for benzene, kf
Based on the cryoscopic constant and the ebullioscopic constant of benzene, we can calculate that the boiling point of this solution will be 82.33 °C.
For this calculation, we require both the cryoscopic constant (Cf = 5.12 °Ckg/mol) and the ebullioscopic constant (Cb = 2.52 °Ckg/mol) for benzene. These describe the shifts in benzene's freezing and boiling points based on the molality of the solution (with benzene as the solvent).
Because we know that the change in benzene's freezing point is 5.53 °C - 1.00 °C = 4.53 °C, we can now calculate the molality of the solution and use it to calculate the boiling point of the same solution.
Δt(freezing) = m * Cf ⇒ m = Δt / Cf = 4.53 °C / 5.12 °Ckg/mol = 0.885 mol/kg
Δt(boiling) = m * Cb = 0.885 mol/kg * 2.52 °Ckg/mol = 2.23 °C
t (boiling) = 80.10 °C + 2.23 °C = 82.33 °C
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Takisha conducted an experiment to determine the effect of salt on the boiling point of water. She measured the boiling points of 100 ml of water with salt added in 5 g increments. As a control, she also recorded the temperature of water with no salt added. What is the purpose of this control?.
A reference value is provided by the control, which can then be compared to the samples in which the value of a variable was altered.
This is further explained below.
What is the purpose of this control?Generally, Control is a management function that aids in mistake detection and the implementation of remedial measures.
This is done to reduce departure from standards and make that the organization's stated objectives are met in the desired way.
In conclusion, The control offers a standard against which samples with varying changes may be measured.
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1. Native copper is a mixture of two isotopes. Copper-63 contributes 69.17% of the atoms of copper and copper-65 the remaining 30.83%. What is the average atomic mass?
Answer: 63.6166 amu (atomic mass units)
Explanation: When an element X is written in the form of X-N, N will the atomic mass of that element. So we have copper with a mass of 63 and 65. We are given percentages of each one. 69.17/100 of the copper atoms will be of weight 63 while 30.83/100 will be of weight 65. Keep in mind that amu does not actually mean weight but I'm just using it as a tool to help explain the general concept. Assume you have 100 copper atoms, and you need to find the average atomic mass for them, if you do this you will solve the problem. Due to the fractions, 69.17 of them will be 63 amu and the rest will be 65. So do 69.17*63+65*30.83 and divide by one hundred. By doing this you will get 63.6166. If my answer doesn't make sense, search up how to calculate weighted averages
Hope this helps
Instant cold packs contain water and chemical called ammonium nitrate. When combined, the ammonium nitrate and water react to create a cold feeling. Is thermal energy absorbed or released during this chemical reaction? Explain
Answer:
Explanation: its cold, so energy is being released to try to reach equal temp with the outside area of the cold pack
In what state is carbon dioxide at 10 °C?
Answer:
Solid
Explanation:
Solid state because carbon dioxide can go sublimation so generally at relatively lower temperature it is found in solid form but at room temperature,ie, 25 to 30°C it is found in gaseous state.
If 5.0g of KCIO3 is decomposed, what volume of O₂ is produced at STP?
2KCIO3 →2KCl +302
The volume of O₂ produced at STP after 5.0g of KCIO3 is decomposed is 1.317L.
What is STP?For experimental measurements to be established under standard conditions that allow for comparisons between various sets of data, standard temperature and pressure must be met. The nominal atmospheric conditions at sea level are referred to as "standard temperature and pressure" (STP). The temperature and pressure are both zero degrees Celsius (atm). STP, or Standard Temperature and Pressure, refers. 2. The STP value of gas temperature, according to IUPAC, is 15 K. 2. According to IUPAC, gas is at 15 K in the STP. VSTP is equal to V* (273.15/T)* (P/760) Kelvins, Torrs, and Liters are used in the STP formula. The number of gas molecules at a standard temperature and pressure, or STP, has been calculated using this law. STP is measured in Kelvin and atmospheres.
39.01 g [tex]mol^{-1}[/tex] + 35.45 g[tex]mol^{-1}[/tex] + 3.1600 g[tex]mol^{-1}[/tex]
= 122.46 g[tex]mol^{-1}[/tex]
To get the material's molecular weight, divide the overall mass of the substance by its relative mass.
5g/ 122.46g[tex]mol^{-1}[/tex] = 0.041mol
There are two moles of KLC[tex]CO_{3}[/tex] for every 3 moles of [tex]O_{2}[/tex] , that can be seen from the equation. Using the ratio 2:3 and inserting 0.048 mol we find that there must be 0.0612 mol [tex]O_{2}[/tex].
At STP (standard temperature and pressure), a mole of an ideal gas takes up 22.4 liters.
Hence
22.4 l[tex]mol^{-1}[/tex] × 0.0612 mol
= 1.317 L
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What is velocity I need help
Answer: the speed of something in a given direction
Explanation:
yuuuuuuh
Answer:
Velocity defines the direction of the movement of the body or the object.
Explanation:
velocity is the speed of motion, action, or operation
If an astronaut moved away from Earth in the direction of the
Moon, how would the gravitational force between Earth and the
astronaut change? How would the gravitational force between the Moon
and the astronaut change?
Gravitational force between the moon and the astronaut change are decrease
The force of attraction between any two bodies is directly proportional to the product of their masses and is inversely proportional to the square of the distance between them
We can visualize the effect mathematically via the equation for newton's law of gravitation
Fgrav = Gm₁m₂/r₂
Fgrav is the magnitude of the gravitational force, in N between two objects G is the gravitational constant means equal to 6.674×10⁻¹¹ N×m²/kg²m₁ and m ₂ are the masses, in kg of the two objects r is the distance in m between the two objectsFrom this relationship, we can see that force Fgrav and square of the distance rare inversely proportional as one increases the other decreases
Therefore, as the distance between the astronaut and earth increases, the magnitude of the gravitational force will decrease
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How does the amount of energy in a wave relate to the amount of danger it poses to living things
The threat to living things increases with decreasing wavelength. While there are risks associated with longer wavelengths as well, live tissue is easily harmed by very short wavelengths like X-rays and gamma rays.
What impact do electromagnetic waves have on living things?The DNA within a living cell can be harmed by some types of electromagnetic radiation, which is radiation present in several types of light waves, including ultraviolet light as well as X-rays. Radiation-induced DNA damage can cause cell death or cancer.
Why are waves and high frequencies bad for living things?Higher-frequency waves have greater energy, and they come in a variety of wavelengths and frequencies. The atmosphere of Earth absorbs gamma rays that come from space. They can obliterate living cells, bring about mutations, and result in cancer. Ironically, gamma rays can be employed to treat cancer despite their lethal effects.
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A metal cube with a volume of 20 cubic centimeters has a mass of 157.48 gram. What is the density of the metal cube?
The density of the metal cube is 7.874 kg/m³
Density is a word we use to describe how much space an object or substance takes up means its volume in relation to the amount of matter in that object or substance means its mass and another way to put it is that density is the amount of mass per unit of volume and if an object is heavy and compact it has a high density
Here given data is metal cube with a volume = 20 cubic centimeters and mass = 157.48 gram so we have to find density of the metal cube = ?
So, density = mass/volume means ρ = m/V
Density = 157.48 gram/20 cubic centimeters
Density = 7.874 kg/m³
The density of the metal cube is 7.874 kg/m³
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Which of the following shows the correctly balanced chemical reaction [tex]H_{2}SO_{4}[/tex] reacting with HI?
The correctly balanced chemical reaction of [tex]H_2SO_4[/tex] with HI is [tex]H_2SO_4 + 8HI -- > H_2S + 4I_2 + 4H_2O[/tex]
Balancing chemical equationsThe equation of chemically balanced reactions must obey the law of conservation.
According to the law of conservation, the number of participating atoms in a reaction must be conserved. In other words, the number before must be the same as after the reaction.
However, the law opines that the forms of atoms may change after reactions.
Sulfuric acid reacts with hydrogen iodide to produce hydrogen sulfide, iodine molecules, and water according to the following equation:
[tex]H_2SO_4 + HI -- > H_2S + I_2 + H_2O[/tex]
However, the equation is yet to obey the law of conservation. The correctly balanced equation of the reaction would be: [tex]H_2SO_4 + 8HI -- > H_2S + 4I_2 + 4H_2O[/tex]
The above equation shows that the number of each atom in the reactants is the same as in the product.
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Which of the following shows the correctly balanced chemical reaction reacting with HI?
a. [tex]H_2SO_4 + 8HI -- > H_2S + 4I_2 + 4H_2O[/tex]
b. [tex]H_2SO_4 + 4HI -- > H_2S + 2I_2 + 2H_2O[/tex]
c. [tex]H_2SO_4 + HI -- > H_2S + I_2 + H_2O[/tex]
A patient needs 50 mg of a medicine three times a day. If each tablet contains 25 mg of medicine the patient will need 20 tablets for a 4-day prescription.
Answer: The Rx should have been filled with 24 tablets, so it is false that the Rx was for 20 tablets
Explanation: 25mg x2 = 50mg x3 (three times a day). So patient takes 150mg day x 4 days= 6 tablets/day for 4 days. Rx should contain 24 tablets. If the pharmacy sent 20, the order wasn't calculated correctly.
Calculate the pH of 1 × 10-2 molar aqueous solution of H2SO4
The pH of a 1 × 10-² molar aqueous solution of H2SO4 is 2.
How to calculate pH?pH is the degree of acidity or alkalinity of a solution. The pH of a solution can be calculated by using the following formula;
pH = - log {H+}
According to this question, the concentration of 1 × 10-² molar aqueous solution of H2SO4. The pH of this solution can be calculated as follows:
pH = - log {0.01}
pH = 2
Therefore, the pH of the aqueous solution is 2.
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Write a paragraph explaining the mechanism of a newton's cradle. Include which law the cradle represents and the forces acting upon it. Also, what are some factors that can prevent the cradle form working?
The Newton Cradle is device that could be used to explain the Newton third law of motion but its working could be hampered by friction.
What is the newton's cradle?We need to recall that Isaac Newton was a scientist whos research centered a lot around the reason for motion. In his studies, we can see that force is the reason for motion. As such, an object tends to move when the object have been acted upon by a system of unbalanced forces.
The Newton Cradle is a system that could be used indicate the principle of the conservation of linear momentum as we can see from the Newton third law. Recall that from the Newton third law; action and reaction are equal and opposite.
Having said this, we can see that the force that acts on one end of the sphere is transmitted across the spheres such that the last sphere across also moves upwards. The sphere could be prevented from working by friction.
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Light of frequency 3.62 x 1015 Hz
strikes a surface of copper
(Wo = 4.70 eV). How much kinetic
energy does the liberated electron
have in eV?
The kinetic energy that the liberated electron has in eV based on the given values is :
10.28 eV.
Explanation:1 eV is the kinetic energy gained by an electron or proton when acted upon by a 1 volt potential difference. E = QV is the formula for energy in terms of charge and potential difference.A photoelectron's maximum kinetic energy is given by
Emax = hf - W
where h is Plank's constant,f is the incident photon's frequency, andW denotes the metal surface's work function.here given,
f = 3.62 x 10¹⁵ Hz
W = 4.70 eV
by recalling the equation for a photoelectron's maximum kinetic energy with given values,
Emax = hf - W
= ((4.14 × 10⁻¹⁵eV.s)(3.62 x 10¹⁵ Hz)) - (4.70 eV)
= 10.28 eV
As a result, we discovered that the maximum kinetic energy of electrons is 10.28eV.
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a solution is made by dissolving 52.0 g of sucrose, c12h22o11, in 117 g of water, producing a solution with a volume of 125 ml at 20°c. what is the expected osmotic pressure at 20°c?
The osmotic pressure is the least amount of pressure that must be applied to a solution in order to block the passage of the solution's pure solvent through a semipermeable membrane. Additionally, it is described as a measurement of a solution's propensity to osmotically absorb a pure solvent.
Temperature and concentration both have an impact on osmotic pressure. Temperature and solute concentration both have an impact on how much pressure is generated when water moves through a membrane. Osmotic pressure rises with temperature and concentration.
The osmotic pressure formula is
Op = C*R*T*i
where, Osmotic pressure is unknown, therefore OP
C = moles/liter of solution multiplied by the molarity of the solution.
Mass of sucrose or molar mass of sucrose equals a mole of sugar.
sucrose mass=52g
Sucrose's molar mass is 342g/mol (C12H22O11).
thus, 52/342 = 0.152 moles of sucrose.
Moles per liter of solution equals the solution's molarity.
117mL*1L/1000mL = 0.117L when converting from 117mL to liters where 1000mL = 1L
the solution's molarity is 0./0.117=1.299M.
R = 0.0821 L atm/mol/K, the universal gas constant.
20 degrees Celsius are converted to Kelvins using the formula T = absolute temperature = degrees in Kelvin. 20+273=293K
The van't Hoff Factor equals 1.
subsequently, the OP = 1.299*0.0821*293*1=31.24atm.
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investigations were carried out in a science lab to explore the topic of chemical and physical changes.
Investigation A
Step 1. Add 5 tsp. salt to 100 ml warm water and stir until most or all of the salt is no longer visible.
Step 2. Heat the salt solution on a burner until only a white solid remains.
Investigation B
Step 1. Mix 10 tsp. white sugar into 100 ml water and stir until most or all of the sugar is no longer visible.
Step 2. Heat the sugar solution on a burner until the solution thickens and turns brown.
In which step(s) did a chemical change most likely occur?
Investigation A, Step 1 and Investigation B, Step 1
Investigation A, Step 2 and Investigation B, Step 2
Investigation A, Step 2 only
Investigation B, Step 2 only
Investigation B, Step 2 only is the one in which a chemical change will most likely occur and is denoted as option D.
What is Chemical change?This is referred to as a type of reaction which is characterized by the formation of a new substance as a result of the synthesis or decomposition of a substance which is referred to as the reactant through various methods and techniques.
In the Investigation B, Step 2, the sugar solution is heated on a burner until the solution thickens and turns brown thereby forming caramel. The chemical change in this scenario is depicted as the caramel which is produced in the process known as caramelisation.
There is a new substance formed which is therefore the reason why option D was chosen as the most appropriate choice.
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Answer:
the answer is BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
Explanation: why? I don't know because I just piked a answer.
timate the enthalpy of vaporization of water at 100°c from its value at 25°c ( 44.01 kj mol−1 ) given the constant-pressure heat capacities of 75.29 j k−1 mol−1 and 33.58 j k−1 mol−1 for liquid and gas, respectively.
vaporization's enthalpy is 40.88 kJ/mol.
What exactly is vaporization enthalpy?The amount of energy (enthalpy) required to turn a portion of a liquid into a gas is known as the enthalpy of vaporization (symbol Hvap), also known as the (latent) heat of vaporization or heat of evaporation.
Enthalpy of vaporization ∆Hvap
T1 = 25 + 273 = 298 K
T2 = 100 + 273 = 373 K
Cp(1) = 0.07529 kJ/K.mol
Cp(2) = 0.03358 kJ/K.mol
So dHvap at 100 oC would be,
dHvap = dHvap at 25 oC + (Cp(2) - Cp(1)(T2-T1)
= 44.01 + (0.03358 - 0.07529)(373-298)
= 40.88 kJ/mol
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the alkoxide group on chymotrypsin that attacks the carbonyl oxygen of the peptide bond of the substrate arises from which active-site amino acid side chain?
The alkoxide group responsible for the nucleophilic attack on the carbonyl group (more precisely the carbon atom) during peptide bond cleavage in chymotrypsin belongs to the serine 195 side-chain.
Because only serine and threonine of all the amino acids contain hydroxy-groups, only they qualify as possible answers. When we look at the structure of the chymotrypsin, we can see that there is a serine 195, so it must be it. Indeed, during peptide bond cleavage, histidine 57 side-chain deprotonates the serine 195 side chain, turning into a nucleophilic hydroxy-group, which can then attack the carbonyl group, held in place by the glycine 193's residue.
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ryan is a chemistry student that enjoys hot tea. he wants to determine how much ice is needed to cool 250.0 ml of tea to an optimal drinking temperature of 57.8 c. macmillan learning the method ryan uses to prepare his tea results in an initial temperature of 79.1 c. the average mass of an ice cube from the ice tray ryan uses is 18.8 g and has a starting temperature of - 8.33 deg * c assume that the heat capacity of tea is the same as pure water, and assume no heat is lost to the surroundings what mass of ice is needed to reach the optimal temperature of 57.8^ c^ prime ?
Ryan calculates that he requires 4 ice cubes for 250mL of hot tea to reach the optimal drinking temperature by using the specific heat capacity of tea.
A substance's potential to hold heat is indicated by its specific heat capacity. This substance size reflects the amount of heat required to raise a certain volume of a material's temperature by one Kelvin. Specific heat capacity is a distinguishing feature of every substance and is useful for material identification.
Given:
Final temperature of system is 57.8℃
dT1 = 79.1 - 57.8 = 21.3℃
dT2 = 0 - (-8.33) = 8.33℃
dT3 = 57.8 - 0 = 57.8℃
Mass of tea, m1 = 250.0mL = 250.0g = 0.250kg
Specific heat capacity of tea, C1 = 4186 J/kg℃ = Specific heat capacity of water
Specific heat capacity of ice, Ci = 2090 J/kg℃
Mass of each ice cubes, m of i = 18.8g
Latent heat of fusion of ice, Lf = 334 kJ/kg
To find:
No. of ice cubes required = ?
Calculations:
Suppose equilibrium temperature is T, then
Heat released by Tea = Heat gained by Ice
Q1 = Q2
m1x C1x dT1 = mi x Ci x dT2 + mi x Lf + mi x Cw x dT3
0.250x 4186 x 21.3 = mi x (2090 x 8.33 + 3.34 x [tex]10^4[/tex] + 4186 x 57.8)
mi = 0.250 x 4186 x 21.3 / (2090 x 8.33 + 3.34 x [tex]10^4[/tex] + 4186 x 57.8)
mi = 0.0761kg = 76.1g
Mass of ice required = 76.1g
Number of ice cube required will be:
n = Total mass of ice/mass of each ice cube
n = 76.1/18.8
n = 4.04 ice cubes = 4.0 ice cubes
Result:
Ryan requires 4 ice cubes to bring 250mL of hot tea to the optimal drinking temperature.
Learn more about Specific heat capacity here:
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For each hydrogen ion concentration listed, calculate the solution as the concentration of hydroxide ion in the solution. Indicate whether each solution is acidic or basic.
(a) [H+] = 4.79*10^-8 M
? M
acidic
basic
neutral
(b) [H+] = 8.90*10^-3 M
?M
acidic
basic
neutral
(c) [H+] = 6.97*10^-5 M
?M
acidic
basic
neutral
(d) [H+] = 1.28*10^-12 M
? M
acidic
basic
neutral
Answer:
basic neural acid neural acid basic