Answer:
[tex]\text{Rate} = k\, [\mathrm{H_2\, (g)}]\cdot [\mathrm{NO\, (g)}]^2[/tex].
[tex]\rm N_2O\, (g)[/tex] is the intermediate.
Explanation:
RateBalanced overall reaction: [tex]\rm 2\, H_2\, (g) + 2\, NO\, (g) \to N_2\, (g) + 2\, H_2O\, (g)[/tex].
Proposed mechanism:
[tex]\rm H_2\, (g) + 2\, NO\, (g) \to N_2O\, (g) + H_2O \, (g)[/tex] (slow.)[tex]\rm N_2O\, (g) + H_2\, (g) \to N_2\, (g) + H_2O\, (g)[/tex] (fast.)Start with the slowest, rate-determining step of the proposed mechanism. Here, the rate-determining step is [tex]\rm H_2\, (g) + 2\, NO\, (g) \to N_2O\, (g) + H_2O \, (g)[/tex].
There are two species on the reactant side of this intermediate reaction: [tex]\rm H_2\, (g)[/tex] and [tex]\rm NO_2\, (g)[/tex]. The concentration of both of them should be in the rate expression of this step.
On the other hand, the coefficient of [tex]\rm H_2\, (g)[/tex] is one while the coefficient of [tex]\rm NO_2\, (g)[/tex] is two. Therefore, in the rate expression of this step, the concentration of [tex]\rm H_2\, (g)\![/tex] should have a power of one, while the concentration of [tex]\rm NO_2\, (g)\![/tex] should have a power of two.
include the rate constant [tex]k[/tex] to obtain the rate expression of the rate-determining slow step:
[tex]\text{Rate} = k\, [\mathrm{H_2\,(g)}]\cdot [\mathrm{NO\, (g)}]^2[/tex].
Make sure that all species in this rate expression are on the reactant side of the overall balanced reaction. Otherwise, further steps would be required to obtain the rate law of the overall reaction.
Therefore, by this proposed mechanism, the rate law of the overall reaction would be [tex]\text{Rate} = k\, [\mathrm{H_2\,(g)}]\cdot [\mathrm{NO\, (g)}]^2[/tex].
IntermediateIn a proposed reaction mechanism, a species is an intermediate if it appeared in one of the proposed steps, but not in the balanced overall equation.
The two steps of this proposed mechanism mentioned five species:
[tex]\rm H_2\, (g)[/tex].[tex]\rm NO\,(g)[/tex].[tex]\rm N_2O\, (g)[/tex].[tex]\rm H_2O\, (g)[/tex].[tex]\rm N_2\, (g)[/tex].With the exception of [tex]\rm N_2O\, (g)[/tex], all the other species appeared in the overall balanced equation. Therefore, [tex]\rm N_2O\, (g)\![/tex] is the intermediate.
Discuss whether each of the following is a mixture or a pure substance. If it is a mixture, please state if it homogeneous or heterogeneous. Please give your reasoning for each case. If it is difficult to tell, explain why.
1. Seawater.
2. Chocolate.
3. Table sugar.
4. An apple.
5. A sheet of paper
6. The spice paprika.
7. Seven Up.
Answer:
Pure substance:
Seven upTable sugarSeawater (H20 + NaCl + impurities)Mixtures:
Chocolate (homogeneous)Paprika spice (homogeneous)Seawater (heterogeneous, because of impurities)A sheet of paper (homogeneous)An apple (heterogeneous)Explanation:
Pure substances exists as either elements or compounds.
A homogeneous mixture has even distribution and a single phase composition of its constituents; whereas heterogeneous mixtures are not uniform and constituents exist in different phases.
How do scientists conduct scientific investigations?
write the balanced nuclear equation for the radioactive decay of radium-226 to give radon-222, and determine the type of decay
Answer: DEAR THE ANSWER TO YOUR QUESTION IS,
Explanation: Consider the equation for the decay of radium-226 to radon-222, with the simultaneous loss of an alpha particle and energy in the form of a gamma ray. Radium-226 is the reactant; radon, an alpha particle, and a gamma ray are the products. The equation is:
shown in the attach figure
TYPE OF DECAY: as α-particle emmit in this reaction hence its the α-decay
It decays by emitting an alpha particle composed of two protons and two neutrons. The radium nucleus turns into radon-222 nucleus, itself radioactive, containing two protons and two neutrons less. The disintegration releases 4.6 million electronvolts of energy
PLS GIVE ME RATING IF YOU FIND IT HELPFULL SO THAT OTHER BE BENIFIT OF THAT ANSWEER
THANKS....
what is the volume in cubic centimeters of a tablet weighing 210 mg
Answer:
1mg=0.001
210
210×0.001÷1
=0.21
What volume, in mL, of 4.50 M NaOH is needed to prepare 250. mL of 0.300 M NaOH?
Answer:
16.7 mL
Explanation:
Convert 250 mL to L.
250 mL = 0.250 L
Calculate the amount of moles of NaOH in 250 mL of 0.300 M NaOH.
0.250 L × 0.300 M = 0.075 mol
Using this amount of moles, you need to find out what volume of 4.50 M will give you that many moles. You can do this by dividing the amount of moles by the molarity.
(0.075 mol)/(4.50 M) = 0.0167 L
Convert from L to mL.
0.0167 L = 16.7 mL
A 50.0 mL sample containing Ni+2 was treated with 25.0 mL of .050 M EDTA to complex all of the Ni+2 and leave some excess EDTA in solution. the excess EDTA was then titrated with .050 M Zn+2, requiring 5.00 mL to reach equivalence point. What was the concentration of Ni+2 in the original solution? (EDTA forms complexes with metals in a 1:1 stoichiometry)
Complete and balance the molecular equation for the reaction between aqueous solutions of ammonium acetate and potassium sulfide.
Answer:[tex]2CH_3COONH_4(aq)+K_2S(aq)\rightarrow 2CH_3COOK(aq)+(NH_4)_2S(aq)[/tex]
Explanation:
A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.
The balanced molecular reaction between aqueous solutions of ammonium acetate and potassium sulfide will be
[tex]2CH_3COONH_4(aq)+K_2S(aq)\rightarrow 2CH_3COOK(aq)+(NH_4)_2S(aq)[/tex]
The balanced molecular equation for the reaction between aqueous solutions of ammonium acetate and potassium sulfide is
[tex]2 CH_3COONH_4(aq) + K_2S(aq) \rightarrow 2 CH_3COOK(aq) + 2 NH_3(g) + H_2S(g)[/tex]
Let's consider the unbalanced molecular equation for the reaction between aqueous solutions of ammonium acetate and potassium sulfide. This is originally a double displacement reaction that would produce potassium acetate and ammonium sulfide. However, ammonium sulfide is unstable and will rapidly decompose into hydrogen sulfide and ammonia.
[tex]CH_3COONH_4(aq) + K_2S(aq) \rightarrow CH_3COOK(aq) + NH_3(g) + H_2S(g)[/tex]
We will balance it using the trial and error method.
We will:
balance K atoms by multiplying CH₃COOK by 2.balance C atoms by multiplying CH₃COONH₄ by 2.balance N atoms by multiplying NH₃ by 2.The balanced molecular equation is:
[tex]2 CH_3COONH_4(aq) + K_2S(aq) \rightarrow 2 CH_3COOK(aq) + 2 NH_3(g) + H_2S(g)[/tex]
The balanced molecular equation for the reaction between aqueous solutions of ammonium acetate and potassium sulfide is
[tex]2 CH_3COONH_4(aq) + K_2S(aq) \rightarrow 2 CH_3COOK(aq) + 2 NH_3(g) + H_2S(g)[/tex]
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2. Determine the molarity of the NaOH solution in each trial. a. Trial 1 Molarity: b. Trial 2 Molarity: 3. Calculate the average molarity of the NaOH solution. 4. Label the volumetric flask containing the NaOH solution with the average molarity.
Answer:
This question is incomplete
Explanation:
This question is incomplete but...
1) You can calculate the molarity of the NaOH for each trial by following the steps below.
The formula for Molarity (M) is
M = number of moles (n) ÷ volume (V)
where the unit of volume must be in Litres or dm³
The unit of molarity is mol/dm³ or mol/L or molar conc (M)
The final answer must have the unit of molarity
If the number of moles is not provided, look out for the mass of NaOH used and then calculate your number of moles (n) as
n = mass of NaOH used ÷ molar mass of NaOH
Where the atomic mass of sodium (Na) is 23, oxygen (O) is 16 and hydrogen (H) is 1. Hence, molar mass for NaOH is 23 + 16 + 1 = 40 g/mol
n = mass of NaOH used ÷ 40
2) Average Molarity will be (Trial 1 Molarity +Trial 2 Molarity) ÷ 2
Answer must be in mol/dm³ or mol/L or M
3) Label the volumentric flask containing the NaOH solution with the answer gotten from (2) above
Would having different atmospheric pressures have an effect on the accuracy of gas laws? If so, which planets would be the most reliable and which would be the least?
Answer:
With the changes in atmospheric pressure, the gas laws also change accordingly, that is, the Charle's law, the Boyle's law, the Ideal Gas Law, and the Gay-Lussac's law changes with the change in atmospheric pressure. Therefore, the planets, which exhibits the constant value of atmospheric pressure will be more reliable, and those possessing different atmosphere or no atmosphere will be the least reliable.
Study the flow diagram below carefully.
Process C
Ethanol
Process A
Heavy
olis
Substance
B
...[2]
(a) Name
(0) Process A.
(ii) Process C
(b) Name substance B
..[1]
[1]
.[1]
(c) Give one significantce of process A
[Total:4]
11 | Page
ProccessA
Explanation:
Ethanol Heavy Oils
If 5.0 mL of a Sports Drink with an absorbance reading of 0.34 was diluted with water to 10.0 mL and was read by the colorimeter, what is the expected absorbance of the solution
Answer:
the expected absorbance of the solution = 0.17
Explanation:
From the information given:
Using Beer's Lambert Law, we have
A = ∈CL
where;
A = Absorbance
∈ = extinction coefficient
C = concentration
L = cell length
Since Absorbance is associated with concentration.
Assuming the measurement were carried out in the same solution; Then ∈ and L will be constant and A ∝ C ----- (1)
Let consider the concentration to be C (mol/L)
5.0 mL of a Sports Drink = 5.0 mL × C (mol)/1000 mL
= 5C/1000 mL
was diluted with water to 10.0 mL
So, when diluted with water to 10.0 mL; we have:
The new concentration to be : [tex]\dfrac{(5 C \times 1000) \ mol }{(1000 \times 10 \times 1000)\ mL}[/tex]
Since :1000mL = 1 L
The new concentration = [tex]\dfrac{C \ mol }{2 \ L}[/tex]
As stated that the initial absorbance reading [tex]A_1[/tex] = 0.34
The expected absorbance reading will be [tex]A_2[/tex] = ???
From (1)
A ∝ C
∴
[tex]\dfrac{A_2}{A_1}=\dfrac{C_2}{C}[/tex]
[tex]A_2 = \dfrac{A_1}{C}[/tex]
[tex]A_2 = \dfrac{0.34}{2}[/tex]
[tex]A_2 = 0.17[/tex]
Thus ; the expected absorbance of the solution = 0.17
Because people have unlimited wants and limited resources, they must
a. recycle and reuse resources.
b. create more resources.
c. make choices about which wants to satisfy.
d. produce more goods and services to satisfy their wants.
Answer:
a
Explanation:
Because they have a limited of thing so they have to reuse resources
Because people have unlimited wants and limited resources, they must recycle and reuse resources. The correct options are a.
What are resources?Resources are things that can be used by an individual or organization to carry out plans and projects. Resources can be natural things and artificial things, like money, raw material, and vehicles. Resources help people to run their life with all peace and ease.
Recycling is the process of gathering and converting resources into new goods that would otherwise be thrown away as waste. Your community and the environment may both benefit from recycling.
The resources are limited on earth and human consumption is increasing day by day. So to proper use of resources, we must reuse and recycle the resources.
Thus, the correct options are a. recycle and reuse resources.
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i need to know the measurements of this to the appropriate amount of significant figures
Answer:
[See Below]
Explanation:
I'd say 44 something. It's probably ml but I can't see what it says on the tube.
Two volatile substances, A and B are dissolved in one another and the resulting solution has a vapor pressure of 137 torr. If the mole fraction of B is 0.230 and the vapor pressure of pure B is 162 torr, what is the vapor pressure of pure A in torr?
Answer:
Vapor pressure of pure A is 129.5torr
Explanation:
When two or more liquids produce an ideal solution, the vapour pressure of the mixture follows the equation (Raoult's law):
[tex]P_T = P_aX_a + P_bX_b[/tex]
Where P is vapour pressure and X mole fraction of liquids A and B. Pt is the pressure of the solution
As mole fraction of B is 0.230, mole fraction of A is:
[tex]1 =X_a+X_b\\1=X_a+0.230\\X_a=0.77[/tex]
Computing in Raoult's law with the given values:
[tex]137 torr= P_a0.77 + 162torr*0.23\\137 torr = 0.77P_a+37.26torr\\99.74torr = 0.77P_a\\P_a=129.5torr[/tex]
Vapor pressure of pure A is 129.5torrThe vapor pressure of pure A in torr is 129.5 torr
How to determine the mole fraction of AMole fraction of B = 0.23 Mole fraction of solution = 1Mole fraction of A =?Mole fraction of A = 1 – 0.23
Mole fraction of A = 0.77
How to determine the vapor pressure of ATotal pressure (P) = 137 torr Mole fraction of B (Xb) = 0.23 Vapor pressure of B (Pb) = 162 torrMole fraction of A (Xa) = 0.77Vapour pressure of A (Pa) =?P = XaPa + XbPb
137 = (0.77 × Pa) + (0.23 × 162)
137 = 0.77Pa + 37.26
Collect like terms
137 – 37.26 = 0.77Pa
99.74 = 0.77Pa
Divide both side by 0.77
Pa = 99.74 / 0.77
Pa = 129.5 torr
Thus, the vapor pressure of pure A is 129.5 torr
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Which of the following statements is not true regarding acids? (2 points) Acids can be corrosive, causing damage to skin or clothing. Many fruits contain weak acids, giving them a sour taste. Acids react with bases in neutralization reactions to produce water. The hydroxide ion concentration is greater than the hydronium ion concentration.
Answer:
Acids do not react with bases in neutralization reactions to produce water.
Explanation:
What is the molar mass of
CH4?
(C = 12.011 amu, H = 1.008 amu)
Answer:
16.0 g/mol (3 s.f.)
Explanation:
Molar mass is the mass of a mole of substance.
1 mole of CH₄ has 1 C atom and 4 H atoms.
Since the molar mass is numerically equal to the molecular mass of a compound, let's find the molecular mass of CH₄ first.
Molecular mass= sum of all the atomic mass in a molecule
Molecular mass of CH₄
= 12.011 amu +4(1.008 amu)
= 16.043 amu
Thus the molar mass of CH₄ is 16.043g/mol, or 16.0g/mol to 3 significant figures.
A) The equilibrium between carbon dioxide gas and carbonic acid is very important in biology and environmental science.
CO2 (aq) + H2O (l) H2CO3 (aq)
Which one of the following is the correct equilibrium constant expression (Kc) for this reaction?
a) K =[H2CO3]/ [CO2]
b) K=[CO2]/ [H2CO3]
c) K=[H2CO3]/ [CO2][H2O]
d) K=[CO2][H2O]/ [H2CO3]
e) K=1/[H2CO3]
B) For the reaction PCl3(g) + Cl2(g) <-->PCl5(g) at a particular temperature, Kc = 24.3. Suppose a system at that temperature is prepared with [PCl3] = 0.10 M, [Cl2] = 0.15 M, and [PCl5] = 0.60 M. Which of the following is true based on the above?
a) Qc > Kc, the reaction proceeds from right to left to reach equilibrium
b) Qc < Kc, the reaction proceeds from right to left to reach equilibrium
c) Qc > Kc, the reaction proceeds from left to right to reach equilibrium
d) Qc < Kc, the reaction proceeds from left to right to reach equilibrium
e) Qc = Kc, the reaction is currently at equilibrium
Answer:
Explanation:
CO₂ (aq) + H₂O (l) ⇄ H₂CO₃ (aq)
Equilibrium constant
Kc = [H₂CO₃] / [CO₂] [H₂O]
B )
PCl₃(g) + Cl₂(g) <--> PCl₅(g)
Kc = 24.3 .
[PCl₃] = .10M ,
[Cl₂] = 0.15 M
[PCl₅] = 0.60 M.
Qc = [PCl₅] / [PCl₃] [Cl₂]
= .60 / .10 x .15
= 40
Qc > Kc
Hence the reaction will proceed from left to right to reach equilibrium . It is so because the product concentration is more .
Option C is the right choice .
Calculate the molarity of a solution containing 9.25 mol H2SO4 in 2.75 L of solution.
A) 9.25
B) 6.50
C) 3.36
D) 25.4
E) 33.6
Answer:
THE MOLARITY OF THE SOLUTION IS 3.36 MOLE/L
Explanation:
First we must understand what molarity is.
Molarity is the number of mole per unit volume of solution. In this question, 9.25 mole of H2SO4 was given in 2.75 L of solution.
Molarity is written in mole per dm3 or L.
So we can calculate the molarity:
9.25 ole of H2SO4 = 2.75 L of solution
The number of mole in 1 L of solution will be:
= 9.25 mole / 2.75 L
= 3.3636 mole/ L
In conclusion, the molarity of the solution is approximately 3.36 mole/L
In this reaction: Mg (s) + I₂ (s) → MgI₂ (s), if 10.0 g of Mg reacts with 60.0 g of I₂, and 57.84 g of MgI₂ form, what is the percent yield?
Answer:
88.1% (to 3 s.f.)
Explanation:
Please see attached picture for full solution.
Which of the saturated solutions below would have the highest [OH- ]? a. M(OH)2 Ksp = 4.25 x 10-6 b. M(OH)2 Ksp = 7.39 x 10-4 c. M(OH)2 Ksp = 2.64 x 10-3 d. M(OH)2 Ksp = 8.52 x 10-8
Answer:
M(OH)2 Ksp = 2.64 x 10-3
Explanation:
Recall that for M(OH)2, its dissolution in water gives;
M(OH)2(s) ----> M^2+(aq) + 2OH^-(aq)
Ksp= x × (2x)^2
Ksp= 4x^3
a)
Ksp= 4.25 x 10^-6
Ksp= 4x^3
x= 3√Ksp/4
x= 3√4.25 x 10^-6/4
x= 1.02 ×10^-2 moldm-3
For 2 OH^- = 2 × 1.02 ×10^-2 moldm-3 = 2.04 ×10^-2 moldm-3
b)
Ksp= 7.39 x 10^-4
Ksp= 4x^3
x= 3√Ksp/4
x= 3√7.39 x 10^-4/4
x= 5.7 ×10^-2 moldm-3
For 2 OH^- = 2 × 5.7 ×10^-2 moldm-3= 11.4 ×10^-2 moldm-3
c)
Ksp= 2.64 x 10^-3
Ksp= 4x^3
x= 3√Ksp/4
x= 3√2.64 x 10^-3/4
x= 8.7 ×10^-2 moldm-3
For 2 OH^- = 2 × 8.7 ×10^-2 moldm-3 = 17.4 ×10^-2 moldm-3
d)
Ksp= 8.52 x 10^-8
Ksp= 4x^3
x= 3√Ksp/4
x= 3√8.52 x 10^-8/4
x= 2.77 ×10^-3 moldm-3
For 2 OH^- = 2 × 2.77 ×10^-3 moldm-3 = 5.54 ×10^-3 moldm-3
Hence, M(OH)2 Ksp = 2.64 x 10-3 has the highest [OH- ].
f 24.7 g of NO and 13.8 g of O₂ are used to form NO₂, how many moles of excess reactant will be left over? 2 NO (g) + O₂ (g) → 2 NO₂ (g)
Answer:
0.02 moles of O₂ will be leftover.
Explanation:
The reaction is:
2NO(g) + O₂(g) → 2NO₂(g) (1)
We have the mass of NO and O₂, so we need to find the number of moles:
[tex] n_{NO} = \frac{m}{M} = \frac{24.7 g}{30.01 g/mol} = 0.82 moles [/tex]
[tex] n_{O_{2}} = \frac{m}{M} = \frac{13.8 g}{31.99 g/mol} = 0.43 moles [/tex]
From equation (1) we have that 2 moles of NO reacts with 1 mol of O₂ to produce 2 moles of NO₂, so the excess reactant is:
[tex] n_{NO} = \frac{2}{1}*0.43 moles = 0.86 moles [/tex]
[tex]n_{O_{2}} = \frac{1}{2}*0.82 moles = 0.41 moles[/tex]
Hence, from above we can see that the excess reactant is O₂ since 0.41 moles react with 0.86 moles of NO and we have 0.43 moles in total for O₂.
The number of moles of excess reactant is:
[tex]n_{T} = 0.43 moles - 0.41 moles = 0.02 moles[/tex]
Therefore, 0.02 moles of O₂ will be leftover.
I hope it helps you!
The number of moles of excess reactant that would be left over is 0.0197 mole
From the question,
We are to determine the number of moles of excess reactant that would be left over.
The given balanced chemical equation for the reaction is
2NO(g) + O₂(g) → 2NO₂ (g)
This means,
2 moles of NO is needed to completely react with 1 mole of O₂
Now, we will determine the number of moles of each reactant present
For NOMass = 24.7 g
Molar mass = 30.01 g/mol
From the formula
[tex]Number\ of\ moles = \frac{Mass}{Molar\ mass}[/tex]
∴ Number of moles of NO present = [tex]\frac{24.7}{30.01}[/tex]
Number of moles of NO present = 0.823059 mole
For O₂
Mass = 13.8 g
Molar mass = 32.0 g/mol
∴ Number of moles of O₂ present = [tex]\frac{13.8}{32.0}[/tex]
Number of moles of O₂ present = 0.43125 mole
Since,
2 moles of NO is needed to completely react with 1 mole of O₂
Then,
0.823059 mole of NO is will react with completely react with [tex]\frac{0.823059 }{2}[/tex] mole of O₂
[tex]\frac{0.823059 }{2} = 0.4115295[/tex]
∴ Number of moles of O₂ that reacted is 0.4115295 mole
This means O₂ is the excess reactant and NO is the limiting reactant
Now, for the number of moles of excess reactant left over
Number of moles of excess reactant left over = Number of moles of O₂ present - Number of moles of O₂ that reacted
∴ Number of moles of excess reactant left over = 0.43125 mole - 0.4115295 mole
Number of moles of excess reactant left over = 0.0197205 mole
Number of moles of excess reactant left over ≅ 0.0197 mole
Hence, the number of moles of excess reactant that would be left over is 0.0197 mole
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2. (01.03 MC)
What energy transfer is occurring when a battery-powered toy rolls across the floor? (3 points)
Stored mechanical energy is converted to thermal energy.
Stored mechanical energy is converted to mechanical energy.
Stored chemical energy is converted to thermal energy.
Stored chemical energy is converted to mechanical energy
Answer:
stored chemical energy is converted into mechanical energy.
Explanation:
the chemical reactions happens in the battery turn into electricity that makes the toy rolls across the floor.
Answer:
stored chemical energy is converted into mechanical energy.
Explanation:
Place the following atmospheric gases in order of abundance, from highest to lowest.
a. Carbon Dioxide
b. Other trace gases
c. Argon
d. Oxygen
e. Nitrogen
Explanation:
The percentage abundance of the following gases in the atmosphere is given as;
Carbon dioxide = 0.04 percent
Other trace gases = about a tenth of one percent of the atmosphere.
Argon = 0.93 percent
Oxygen = 21 percent
Nitrogen = 78 percent
Te order from highest to lowest is given as;
Nitrogen
Oxygen
Argon
Carbon dioxide
Other trace gases
Three 15.0-mL acid samples—0.10 M HA, 0.10 M HB, and 0.10 M H2C¬are all titrated with 0.100 M NaOH. If HA is a weak acid, HB is a strong acid, and H2C is a diprotic acid, which statement is true of all three titrations?
Answer:
All three titrations require the same volume of NaOH to reach the first equivalence point.
Explanation:
Statements are:
All three titrations have the same final pH.
All three titrations require the same volume of NaOH to reach the first equivalence point.
All three titrations have the same pH at the first equivalence point.
All three titrations have the same initial pH.
The pH of the titration depends of the nature of the acid: If the acid is a strong acid, pH at the equivalence of the titration is 7. For a weak acid equivalence point depends of the nature of the conjugate base and initial pH of the weak acid. For a diprotic acid also depends of the nature of the acid.
Thus:
All three titrations have the same initial pH, All three titrations have the same pH at the first equivalence point. and All three titrations have the same final pH. are the three FALSE.
As the concentrations of the acids is 0.10M and are titrated with 0.100M NaOH, The volume to reach the first equivalence point is the same for all the three acids.
Thus:
All three titrations require the same volume of NaOH to reach the first equivalence point.A 0.010 M aqueous solution of a weak acid HA has a pH of 4.0. What is the degree of ionization of HA in the solution
Answer:
[tex]\alpha =0.0009995[/tex]
Explanation:
Hello,
In this case, given the pH of the weak acid HA, we can obtain the concentration of hydrogen in the solution as shown below:
[tex]pH=-log([H^+]})[/tex]
[tex][H^+]=10^{-pH}=10^{-4.0}=1x10^{-4}M[/tex]
In such a way, the degree of ionization ([tex]\alpha[/tex]) is computed as:
[tex]Ka=\frac{\alpha ^2C_0}{1-\alpha}[/tex]
Whereas [tex]C_0[/tex] is 0.010 M and the acid dissociation constant is:
[tex]Ka=\frac{(1x10^{-4})^2}{1-1x10^{-4}}=1x10^{-4}[/tex]
Thus, solving for [tex]\alpha[/tex], we obtain:
[tex]\alpha =0.0009995[/tex]
Regards.
What indicators of a chemical reaction occurred in the following equation?
C6H12O6 (s) + 602 (g) → 6 CO2 (g) + 6H2O (1) +
energy
Answer:
1) evolution of gas
2) evolution of heat
Explanation:
In this reaction, glucose is broken down into its constituents; carbon dioxide and water. The question is to decipher indicators of a chemical reaction from the equation.
If we look at the equation carefully, we will notice that a gas was evolved (CO2). The evolution of a gas indicates that a chemical reaction must have taken place. Secondly, energy is given off as heat. This is another indication that a chemical reaction has taken place.
Identify the Brønsted acid in the following equation:
H2SO4(aq) + 2NH3(aq)
(NH4)2SO4aq
Answer:
H₂SO₄
Explanation:
A Brønsted acid is a proton donor. It loses protons.
This equation may be easier to understand if we write it ionically.
[tex]\underbrace{\hbox{H$_{2}$SO$_{4}$}}_{\hbox{Br$\o{}$nsted acid}} + 2 \text{NH}_{3} \longrightarrow \, \underbrace{\hbox{SO$_{4}^{2-}$}}_{\hbox{Br$\o{}$nsted base}} + \text{2 NH}_{4}^{+}[/tex]
We see that the H₂SO₄ has lost two protons to become SO₄²⁻, so it is a Brønsted acid.
Calculate the solubility of Co(OH)2, in g/L, in solutions that have been buffered to the following pHs.
Ksp=1.6*10^-15.
a. 7.00
b. 10.00
c. 4.00
Answer:
a. 14.9g/L
b. 1.49x10⁻⁶
c. 1.49x10⁷
Explanation:
You can write the buffer Ksp of Co(OH)₂ as follows:
Co(OH)₂(s) ⇄ Co²⁺ + 2OH⁻
Ksp = 1.6x10⁻¹⁵ = [Co²⁺] [OH⁻]²
To have buffered the solutions means [OH⁻] is fixed. From the equilibrium of water we can relate [OH⁻] with pH as follows:
[OH⁻] = 10^[14-pH]
With [OH⁻] and Ksp we can solve for [Co²⁺]. Its concentration is equal to solubility (That is the amount of Co(OH)₂ that can be dissolved).
[Co²⁺] is in mol/L. With molar mass of Co(OH)₂ -92.948g/mol-, We can obtain, in the end, its solubility in g/L.
-Molar concentration of [Co²⁺] and solubility:
a. [OH⁻] = 10^[14-7.00] = 1x10⁻⁷
[Co²⁺] = 1.6x10⁻¹⁵ / [1x10⁻⁷]²
[Co²⁺] = 0.16mol / L = Solubility.
In g/L = 0.16mol / L ₓ(92.948g/mol) =
14.9g/L
b. [OH⁻] = 10^[14-10.00] = 1x10⁻⁴
[Co²⁺] = 1.6x10⁻¹⁵ / [1x10⁻⁴]²
[Co²⁺] = 1.6x10⁻⁸mol / L = Solubility.
In g/L = 1.6x10⁻⁸mol / L ₓ(92.948g/mol) =
1.49x10⁻⁶g/L
c.[OH⁻] = 10^[14-4.00] = 1x10⁻¹⁰
[Co²⁺] = 1.6x10⁻¹⁵ / [1x10⁻¹⁰]²
[Co²⁺] = 1.6x10⁵mol / L = Solubility.
In g/L = 1.6x10⁵mol / L ₓ(92.948g/mol) =
1.49x10⁷g/L
As you can see, and as general rule, all hydroxides are solubles in acids.
The d orbital electron configuration of octahedral complexes can either be described as high- spin with the maximum possible number of unpaired d-electrons, or low-spin containing one or more paired d-electrons. [Fe(H20)s]2 is a high-spin octahedral complex. What is its spin- state (S-?)? Draw a d-orbital splitting diagram for this complex and fill it with the appropriate number of electrons. Where does the final electron go in this diagram? If you were to oxidize this molecule do you think this would affect the bond lengths? Explain
Answer:
See explanation
Explanation:
Fe(H20)6]2+ is a high spin octahedral complex because water is weak field ligand. A high spin complex has a maximum number of unpaired d electrons.
The spin state of Fe(H20)6]2+ is S=2. The final electron goes into an eg orbital. If the metal is oxidized to Fe^3+, the bond lengths decreases. For an oxidation of M2+ complex to M3+, the M3+L bonds will be shorter due to the higher charge density on the metal. Since the occupation of the eg orbitals in both complexes is the same it then follows that that the difference in the bond lengths must be due to the charge alone.
Consider the words or phrases below and drop them in the bucket that you would most associate with the word or phrase in the thermodynamic context. In cases where you think they could go in two buckets, consider (even write down) what conditions are necessary for each condition. Thermo is all about the conditions...
Group the following words into
1. non equilibrium,
2 equilibrium phase cahnge, and
3. equilibrium reaction.
Heat of vaporization
saturated solution
mass movement
unsaturated solution
condensation
heat of fusion
vapor pressure
normal boiling poin
Ksp
solubility
Ka
Answer:
1) non equilibrium
mass movement
unsaturated solution
2)equilibrium phase change
Heat of vaporization
condensation
heat of fusion
normal boiling point
vapor pressure
3) equilibrium reaction
saturated solution
Ksp
solubility
Ka
Explanation:
Nonequilibrium processes are those processes that are irreversible. They often lead to an increase in entropy of the system.
In chemical systems, a state of equilibrium is said to have been attained when the rate of the forward process equals the rate of the reverse process. This is true for both chemical reaction and phase changes. A state of equilibrium connotes a constancy in physical properties of a system over a period of time.