Answer:
The pH of the buffer is 3.90
Explanation:
The mixture of a weak acid CH3COOH and its conjugate base CH3COO produce a buffer that follows the equation:
pH = pKa + log [A-] / [HA]
Where pH is the pH of the buffer, pKa is the pKa of acetic acid (4.75), and [A-] could be taken as the moles of the conjugate base and [HA] the moles of thw weak acid.
To solve this question we need to find the moles of the CH3COOH and CH3COO- after the reaction with HCl:
CH3COO- + HCl → CH3COOH + Cl-
The moles of CH3COO- are its initial moles - the moles of HCl added
And moles of CH3COOH are its initial moles + moles HCl added
Moles CH3COO-:
Initial moles = 0.100L * (0.010mol / L) = 0.00100moles
Moles HCl = 0.010L * (0.050mol / L) = 0.000500 moles
Moles CH3COO- = 0.000500 moles
Moles CH3COOH:
Initial moles = 0.100L * (0.040mol / L) = 0.00400moles
Moles HCl = 0.010L * (0.050mol / L) = 0.000500 moles
Moles CH3COO- = 0.003500 moles
pH is:
pH = 4.75 + log [0.000500] / [0.00350]
pH = 3.90
The pH of the buffer is 3.90
The pH of the buffer after addition of 10.0 mL of 50.0mM HCl is 3.90
What is the Henderson-Hasselbach equation?The Henderson-Hasselbach equation is given as:
pH = pKa + log [A-] / [HA]where
pKa of acetic acid (4.75), [A-] is moles of the conjugate base[HA] the moles of thw weak acid.How to determine the moles of CH3COO- and CH3COOHThe formula for calculating number of moles is:
Moles = concentration × volumeThe equation of the reaction is given below:
CH3COO- + HCl → CH3COOH + Cl-
moles of CH3COO- = initial moles - moles of HCl added
moles of CH3COOH = initial moles + moles HCl added
Moles CH3COO-
Molarity = 0.010 M
volume = 100 mL = 0.100 L
Initial moles = 0.100 L * 0.010 M = 0.001 moles
Moles HCl = 0.010L * 0.050 M= 0.0005 moles
Moles CH3COO- = 0.001 - 0.0005 moles
Moles of CH3COO- = 0.000500 moles
Moles CH3COOH:
Molarity = 0.040 M
volume = 100 mL = 0.100 L
Initial moles = 0.100L * (0.040mol / L) = 0.00400moles
Moles HCl = 0.010L * (0.050mol / L) = 0.000500 moles
Moles CH3COO- = 0.004 - 0.0005 moles
Moles CH3COO- = 0.003500 moles
Substituting the calculated values:
pH = 4.75 + log [0.000500] / [0.00350]
pH = 3.90
Therefore, the pH of the buffer after addition of the 10.0 mL 50.0mmHg HCL is 3.90
Learn more about about buffers and pH at: https://brainly.com/question/11851669
Which of the following represents C3H8?
Among the given options the compound with the formula C₃H₈ is option C. It is an organic compound under named as propane.
What is propane?
Propane is an organic compound classified as a hydrocarbon with saturated carbon - hydrogen bonds. It's formula is C₃H₈. It contains 3 carbons and 8 hydrogens.
The two end carbons contains 3 hydrogens each and the middle carbon contains 2 hydrogens. They are all bonded through sigma bonding. The compound in A is C₅H₁₂ and in B, it is C₆H₁₄.
The formula of the compound in option D is C₅H₁₀. Hence, the skeleton showing the compound with the formula of C₃H₈ is option C.
To find more on propane, refer here:
https://brainly.com/question/24159489
#SPJ2
Apply: Click Reset. Set m to 1.0 kg, L to 2.0 m, g to 9.8 m/s2, and θ to –40 degrees. What is the maximum velocity of this pendulum? Show your work. (Hint: The exact height of the pendulum is now 0.468 m.)
Answer:
[tex]3.029\ \text{m/s}[/tex]
Explanation:
m = Mass of pendulum = 1 kg
L = Length of pendulum = 2 m
g = Acceleration due to gravity = [tex]9.8\ \text{m/s}^2[/tex]
h = Height of the pendulum = 0.468 m
[tex]\theta[/tex] = Angle of deflection = [tex]-40^{\circ}[/tex]
[tex]\cos\theta=\dfrac{L-h}{L}\\\Rightarrow h=L-L\cos\theta\\\Rightarrow h=L(1-\cos\theta)\\\Rightarrow h=2(1-\cos(-40))=0.468\ \text{m}[/tex]
The energy balance of the pendulum is as follows
[tex]mgh=\dfrac{1}{2}mv^2\\\Rightarrow v=\sqrt{2gh}\\\Rightarrow v=\sqrt{2\times 9.8\times 0.468}\\\Rightarrow v=3.029\ \text{m/s}[/tex]
The maximum velocity of this pendulum is [tex]3.029\ \text{m/s}[/tex].
Answer:
Max velocity = 3.03 m/s
Explanation:
Mgh = ½ mv2
(1 kg)(9.8 m/s2)(0.468 m) = ½ (1 kg) v2
2 x 4.5864 = ½ v2 x 2
√V2 = √9.1728
V = 3.03 m/s
I hope this helps!
One mole of a metallic oxide reacts with one mole of hydrogen to produce two moles of the pure metal
and one mole of water. 5.00 g of the metallic oxide produces 2.32 g of the metal. What is the metallic
oxide? (Use molar masses)
Answer:
Lithium oxide, Li₂O.
Explanation:
Hello!
In this case, according to the given amounts, it is possible to write down the chemical reaction as shown below:
[tex]M_2O+H_2\rightarrow 2M+H_2O[/tex]
Which means that the metallic oxide has the following formula: M₂O. Next, we can set up the following proportional factors according to the chemical reaction:
Thus, we perform the operations in order to obtain:
[tex]\frac{10X}{(2X+16)}=2.32[/tex]
So we solve for x as shown below:
[tex]10X=2.32(2X+16)\\\\10X=4.64X+37.12\\\\X=\frac{37.12}{10-4.64}\\\\X= 6.93g/mol[/tex]
Whose molar mass corresponds to lithium, and therefore, the metallic oxide is lithium oxide, Li₂O.
Best regards!
Fill the plastic cup half full with room-temperature water, and drop in the whole tablet. Use a stopwatch to measure how long it takes the tablet to dissolve completely. Record your observation.
Answer:
it bubbles up and has a chemical reaction also releases co2
Explanation:
Hope it helps <3
This group of fungi forms spores in a round structure on the end of a hyphae
Answer:
Is zygote fungi an option??
Answer:
zygote fungi
Explanation:
i got the answer right
Read the list of common household substances.
Yogurt, soaps, window cleaner, vinegar
Which of these substances are likely to have a slippery feel? (1 point)
Yogurt, soaps
Yogurt, vinegar
Soaps, window cleaner
Window cleaner, vinegar
Answer:
A
Explanation:
Please answer this. List the three most abundant minerals in this bottle of mineral water.
How many molecules in 4.10 mol H2O?
6.02×10^23
1.4×10^23
2.47×10^24
1.15×10^-23
Answer:
2,47 * [tex]10^{24}[/tex] (molecules)
Explanation:
Avogadro's number is a very important relationship: 1 mole = 6,02 * [tex]10^{23}[/tex] atoms, molecules, protons, etc.
To convert from moles to molecules, multiply the molar amount by Avogadro's number.
4,1 mol * 6,02 * [tex]10^{23}[/tex] ≈ 24,7 * [tex]10^{23}[/tex] = 2,47 * [tex]10^{24}[/tex] (molecules)
Therefore the third answer is correct
Which of the following involves a reaction in which energy is absorbed?
O A. An instant cold pack
O B. A car's engine
C. A chemical hand-warmer
O D. A campfire
33) Which is the correct name for the molecule depicted below?
A. 2-isopropyl-2,3,4-trimethylbutane
B. 2-isopropyl-2,3-dimethylpentane
C. 2,3,3,4-tetramethylhexane
D. 1,1,2,2,3-pentamethylpentane
E. None of these choices is correct.
Answer:
C. 2,3,3,4-tetramethylhexane
Explanation:
What is the definition of lava?
Answer:
Lava, magma (molten rock) emerging as a liquid onto Earth's surface. The term lava is also used for the solidified rock formed by the cooling of a molten lava flow.
Explanation:
What is the percent oxygen in Rb2Cr2O7
Answer:
28.9452
Explanation:
Answer:
28.9452%
Explanation:
Rb-44.1781
Cr-26.8767
O-28.9452
A
regulation
NBA
basketball
has
a
surface
area
of 283 square inches
.
What
is
the
surface
area
of
this
basketball
in Square Centimeters
?
Answer:
1.83 × 10³ cm²
Explanation:
Step 1: Given data
Surface area of a NBA basketball (A): 283 in²
Step 2: Convert "A" from square inches to square centimeters
In order to convert "A" from in² to cm², we need a conversion factor. In this case, we will use the conversion factor 1 in = 2.54 cm. Since "in" is raised to the power of 2, we will have to raise the conversion factor to the power of 2 as well.
283 in² × (2.54cm/1 in)² = 1.83 × 10³ cm²
Which of the following substances contains MOSTLY ionic bonding? A) LIF B) CO2 C) AICI: D) BeCl2 E) Cu
Answer: [tex]LiF[/tex] , [tex]AlCl_3[/tex] and [tex]BeCl_2[/tex]
Explanation:
An ionic bond is formed when an element completely transfers its valence electron to another element. The element which donates the electron is known as electropositive element or the metal and the element which accepts the electrons is known as electronegative element or non metal.
A covalent bond is formed when an element shares its valence electron with another element. This bond is formed between two non metals.
[tex]LiF[/tex] , [tex]AlCl_3[/tex] and [tex]BeCl_2[/tex] contain ionic bonds as they aremade up of metals and non metals.
Which of the following represent chemical processes? Which represent physical processes?
A). Calcium chloride dihydrate (CaCl2 * 2H2O) slowly heated in a crucible to become calcium chloride (anhydrous).
B). A hydrocarbon such as propane (C3H8) undergoes combustion to power a grill
C). A rock climber’s rope becomes frayed and turns the color of the rocks
D). A dog urinates on an air conditioner coil and the coil becomes corroded
Answer:
A). Calcium chloride dihydrate (CaCl2 * 2H2O) slowly heated in a crucible to become calcium chloride (anhydrous).
Dehyration is a physical process
B). A hydrocarbon such as propane (C3H8) undergoes combustion to power a grill
Combustion is a chemical process.
C). A rock climber’s rope becomes frayed and turns the color of the rocks
This is physical process
D). A dog urinates on an air conditioner coil and the coil becomes corroded
Corrsion is a chemical process.
Explanation:
The chemical process is combustion and corrosion i.e. B and D. The physical change has been the heating of calcium chloride, and fraying of rock i.e. A and C.
A chemical process has been given as the reaction in which the composition of the sample changes. It has been an irreversible process.
A physical process has been described as a change in the physical properties of substances. It is a reversible process.
The following reaction can be given as:
A. The reaction between calcium chloride and water has been mediated by heating. It is a reversible process and does not change the chemical composition. It is a physical process.
B. The combustion results in the change in the chemical constituents of propane. It is a chemical process.
C. There has been no change in the chemical composition of materials. It has been a physical process.
D. The corrosion has resulted from the chemical change in the iron. It has been a chemical process
Thus, the chemical process is combustion and corrosion. The physical change has been the heating of calcium chloride, and fraying of rock.
For more information about the chemical process, refer to the link:
https://brainly.com/question/1286014
Indicate the type of solute-solvent interaction that should be most important in each of the following solutions.a. LiCl in waterb. NF3 in acetonitrile (CH3CN)c. CCl4 in benzene (C6H6)d. methylamine (CH3NH2) in watere. Dispersion forcesf. Dipole-dipole forcesg. Ion-dipole forcesh. Hydrogen bonding
Explanation:
a. LiCl is an ionic molecule whereas water is a polar molecule with net dipole moment in it. There LiCl in water would have an ion-dipole force of interaction.
b. Both NF3 and CH3CN have dipole moment in them, since both are polar molecule. Hence, there would be dipole-dipole interaction.
c. Here both CCl4 and benzene are non polar molecules therefore, they have London dispersion force of interaction.
d. In methylamine and water both have hydrogen bonding in them. The nitrogen of CH3NH2 forms hydrogen bond with water.
The type of interactions in the following solutions are:
LiCl in water - Ion-dipole force[tex]\rm NF_3[/tex] in acetonitrile - Dipole-dipole force[tex]\rm CCl_4[/tex] in benzene - London Dispersion forceMethylamine in water - Hydrogen bondingIn a solution, the dissolution of solute molecules is driven by the interactions between the solute and solvent molecules.
Which interaction is present in solutions?The solute solvent interaction is based on the nature of the molecules. The interactions in the following solutions are:
LiCl in waterThe water is polar solvent and LiCl is an ionic molecule. The interaction between the molecules will be Ion-dipole force.
[tex]\rm NF_3[/tex] in acetonitrileThe acetronitrile and [tex]\rm NF_3[/tex] both are polar molecules. The force present in the interactions is Dipole-dipole force.
[tex]\rm CCl_4[/tex] in benzeneThe benzene and [tex]\rm CCl_4[/tex] both are nonpolar molecules. The type of interaction present in the solution is London Dispersion force.
Methylamine in waterThe water is a polar solvent, and Methylamine is an organic compound. The interaction in the solution is hydrogen bonding.
Learn more about solute-solvent interactions, here:
https://brainly.com/question/14281527
When 42.5 g of benzamide (C7H7NO) are dissolved in 500 g of a certain mystery liquid X, the freezing point of the solution is 6.40 °C less than the freezi point of pure X. Calculate the mass of iron(III) nitrate (Fe(NO3)3 that must be dissolved in the same mass of X to produce the same depression in freezing point.
Answer:
21.3g of Fe(NO₃)₃ are required to produce the same depression in freezing point of solution.
Explanation:
Freezing point depression is a colligative property which indicates, in determined mixture, the freezing point of solution is lower that the freezing point of the solvent, according the amount of solute.
Formula is: ΔT = Kf . m . i
Kf is the cryoscopic constant, which is particular for each solvent. We do not have that data, so we need to find it out in order to solve the question:
ΔT = Freezing point of pure solvent - Freezing point of solution.
This data is known → 6.40°C
m, means molality, moles of solute in 1kg of solvent. Let's get the moles of benzamide: 42.5 g . 1mol / 121g = 0.351 moles
m = 0.351 mol / 0.5kg = 0.702 m
As benzamide is an organic compound i, = 1. i are the number of ions dissolved in solution. Let's find out Kf:
6.40°C = Kf . 0.702 m . 1
6.40°C /0.702m = 9.11 °C/m.
Let's go to the next question.
ΔT is the same → 6.40°C
But this is, an inorganic salt, a ionic salt: Fe(NO₃)₃ → 1Fe³⁺ + 3NO₃⁻
For this case, we have 1 mol of Iron(III) and 3 nitrates, so i = 4
Let's replace data: 6.40°C = 9.11 °C/m . m . 4
6.40°C / (9.11 m/°C . 4) = 0.176 m
This data represents that, in 1 kg of solvent we have 0.176 moles of nitrate.
Mass of solvent X required in this case is 0.500 kg, so, the moles that are contained are: 0.500 kg . 0.176 mol/kg = 0.088 mol
Let's determine the mass of salt: 0.088 mol . 241.85g /1mol = 21.3 g
A sample consisting of 65.0 g of xenon is confined in a container at 2.00 atm and 298 K and then allowed to expand adiabatically (a) reversibly to 1.00 atm, (b) against a constant pressure of 1.00 atm. Calculate the final temperature and the expansion work at each case. Use the fact that xenon is a monoatomic gas.
Answer:
[a]. - 445.45J,
[b]. - 367.92 J
Explanation:
The following parameters are given in the question above. These information are used in solving this problem.
The mass of Xenon = 65.0 g of xenon, pressure = 2.00 atm, temperature = 298 K.
The number of moles of xenon = mass/ molar mass = 65g/ 131.293= 0.495.
The cp= 3/2 R, cp =3/2R + R = 5/2 R.
j = cp/cv = 3/2.
[a]. The final temperature,T2 = (2)^-2/3 × (298)^5/3 = T2^5/3.
Final temperature,T2 = 225.84K.
Expansion work = nCv [ T₂ - T₁] = 0.495 × 3/2 × 8.314 × [ 225.84 - 298] = - 445.45J.
(b). The final temperature can be Determine as;
3/2( T2 - 298k) = - 1 (T2 /1 - 298/2).
3/2(T2 - 298) = - T2 + 149K.
3T2 - 894 = - 2T2 +298K.
T2 = 238.4 K.
Workdone= nCv (T2 - T1) = 0.495 × 3/2 × 8.314 (238.4 - 298) = - 367.92 J.
Can somebody PLEASE tell me the empirical formula for br2o6
Answer:
BrO3
Explanation:
The empirical formula is the smallest whole-number ratio, you find the greatest common factor (which is 2, in this case), then divide the subscripts by it.
So:
Br2 / 2 = Br1
O6 / 2 = O3
if a gas at 300k occupies 3.60 liters at a pressure of 1.00 atm, what will be it’s new pressure if the volume is compressed to 2.0 liters at a temperature of 450K?
Answer: The new pressure if the volume is compressed to 2.0 liters at a temperature of 450K is 2.7 atm
Explanation:
The combined gas equation is,
[tex]\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}[/tex]
where,
[tex]P_1[/tex] = initial pressure of gas = 1.00 atm
[tex]P_2[/tex] = final pressure of gas = ?
[tex]V_1[/tex] = initial volume of gas = 3.60 L
[tex]V_2[/tex] = final volume of gas = 2.0 L
[tex]T_1[/tex] = initial temperature of gas = [tex]300K[/tex]
[tex]T_2[/tex] = final temperature of gas = [tex]450K[/tex]
Now put all the given values in the above equation, we get:
[tex]\frac{1.00\times 3.60}{300}=\frac{P_2\times 2.0}{450}[/tex]
[tex]P_2=2.7atm[/tex]
The new pressure is 2.7 atm
Ways in which ions may form include
Answer:
Ions are formed by the addition of electrons to, or the removal of electrons from, neutral atoms or molecules or other ions; by combination of ions with other particles; or by rupture of a covalent bond between two atoms in such a way that both of the electrons of the bond are left in association
The ways Ions may form includes the following
The addition of electrons to neutral atoms or moleculesThe removal of electrons from neutral atoms or molecules By combination of ions with other particlesWhen the number of protons does not equal the number of electrons in an atomMeaning of an IonAn ion can be defined as an atom or group of atoms possessing an electrical charge. Ions are of two types, they are : Anions which are negatively charged and Cations which are positively charged.
In conclusion, an ion can be formed by many ways, but a few has been listed above.
Learn more about ions : https://brainly.com/question/14511468
#SPJ2
Can someone help me with this
Answer:
a
b
d
c
Explanation:
eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee (so bot sees more so thinks it explain)
A formula unit made with Na and unknown nonmetal "Z" has the formula, NaZ. Which element does "Z" represent?
In which state of matter are the particles at rest (not moving at all)?
none of these
solid
liquid
gas
Answer:
Solids for sure
particles of solid cant flow.
Answer:
B)Solids
Solids have tightly packed particles unlike liquids and gases whose particles can move freely but rate of movement is highest in gas while compared to water
Over an interval of 2.0 s the average rate of change of the concentration of C was measured to be 0.0540 M/s. What is the final concentration of A at the end of this same interval if its concentration was initially 2.000 M
Answer:
Explanation:
the average rate of change of the concentration =
( initial concentration - final concentration ) / time
Initial concentration = 2.000 M
the average rate of change of the concentration = .0540 M/s
time = 2 s
Putting the values
.0540 = (2.000 - X ) / 2
0.108 = 2.000 - X
X = 1.892 M .
Final concentration = 1.892 M .
According to the Bohr model of the atom, which particles are allowed to exist in any one of a number of energy levels?
Answer: the line-emission spectrum of an atom is caused by the energies released when electrons. releases energy of only certain values.
The formation of tert-butanol is described by the following chemical equation: Suppose a two-step mechanism is proposed for this reaction, beginning with this elementary reaction: Suppose also that the second step of the mechanism should be bimolecular. Suggest a reasonable second step. That is, write the balanced chemical equation of a bimolecular elementary reaction that would complete the proposed mechanism.
Answer:
(CH3)3C^+ + OH^- --------> (CH3)3COH
Explanation:
This reaction has to do with SN1 reaction of alkyl halides. Here tert-butanol is formed from tert-butyl bromide.
The first step in the reaction is the formation of a carbocation. This is a unimolecular reaction. The rate of reaction depends on the concentration of the alkyl halide. This is a slow step and thus the rate determining step in the mechanism.
(CH3)3CBr -------> (CH3)3C^+ + Br^-
The second step is a fast step and it completes the reaction mechanism. It is a bimolecular reaction as follows;
(CH3)3C^+ + OH^- --------> (CH3)3COH
What is the energy of an electron in the third energy level of hydrogen?
Answer:
Electrons in a hydrogen atom must be in one of the allowed energy levels. If an electron is in the first energy level, it must have exactly -13.6 eV of energy.
...
Energy Levels of Electrons.
Energy Level Energy
1 -13.6 eV
2 -3.4 eV
3 -1.51 eV
4 -.85 eV
After adding 20.0 mL of 5% NaOH solution into the remaining organic layer, followed by mixing and venting, the solution separated into two distinct layers. Match the following:
1. The top layer was the ______________ layer.
2. 9-fluorenone was most soluble in the ____________ layer.
3. Deprotonated chloroanilic acid was most soluble in the _____________ layer.
4. The bottom layer was the __________________ layer.
5. The organic layer was a ________________ colored solution.
6. The aqueous layer turned into a _____________ colored solution.
a. organic
b. aqueous
c. yellow
d. pink
Answer:
Explanation:
The objective of this experiment is to match the expected result with each of the propositions given after the experiment had been carried out.
1. The top layer was the organic layer. This is because all the organic compounds have lesser density than water except chloroform that will be formed when NaOH is added.
2. 9-fluorenone was most soluble in the organic layer. This is so as a result of its non-polar carbon structure.
3. Deprotonated chloroanilic acid was most soluble in the aqueous layer as a result of the formation of an electrovalent bond with water.
4. The bottom layer was the aqueous layer as a result of the huge amount of water density.
5. The organic layer was a yellow colored solution.
6. The aqueous layer turned into a pink colored solution.
How are the smallest ocean waves produced?
Answer:
The moon is not pulling the tide as hard
Explanation:
I suppose, I know it dills with the moon though
Explanation:
Normalmente, las olas se forman por el viento aunque su historia comienza muy lejos, en el Sol. ... Cuando el viento sopla sobre el mar, las partículas de aire rozan a las partículas de agua y se empiezan a formar pequeñas olas de pocos milímetros de longitud, llamadas ondas capilares.
Normally, waves are formed by the wind, although their history begins very far away, in the Sun. ... When the wind blows over the sea, the air particles brush against the water particles and small waves of few millimeters in length, called capillary waves.