Answer:
K = 8.6x10⁻⁶
Explanation:
a chemist finds that a 5.2L reaction vessel...
To solve this question we need first to find the equation of the equilibrium constant using the chemical eqiation:
TiCl₄(l) ⇄ Ti(s) + 2Cl₂(g)
The equilibrium constant expression is:
K = [Cl₂]²
Because equilibrium constant is defined as the ratio berween concentrationa of products over reactant powered to its reaction coefficient. But pure liquids as TiCl₄(l) and pure solids as Ti(s) are not taken into account
Now, we need to find the molar concentration of Cl₂, [Cl₂]:
Moles Cl₂ -Molar mass: 70.9g/mol-:
1.08g * (1mol / 70.9g) = 0.0152 moles / 5.2L =
2.93x10⁻³M = [Cl₂]
K = (2.93x10⁻³)²
K = 8.6x10⁻⁶Tris is a molecule that can be used to prepare buffers for biochemical experiments. It exists in two forms: Tris (a base) and TrisH (an acid). The MW of Tris base is 121.14 g/mol; the MW of TrisH is 157.6 g/mol (the extra weight is due to the Cl- counterion that is present in the acid). The Ka of the acid is 8.32 X 10-9. Assume that you have TrisH in solid form (a powder), unlimited 1M HCl, unlimited 1 M NaOH and an unlimited supply of distilled water. How would you prepare 1 L of a 0.02 M Tris Buffer, pH
Solution :
The reaction :
[tex]$\text{TrisH}^+ + \text{H}_2\text{O} \rightarrow \text{Tris}^- +\text{H}_3\text{O}^+$[/tex]
We have
[tex]$K_a = \frac{[\text{Tris}^-]\times[\text{H}_3\text{O}^-]}{[\text{TrisH}^+]}$[/tex]
[tex]$=\frac{x^2}{0.02-x}$[/tex]
[tex]$= 8.32 \times 10^{-9}$[/tex]
Clearing x, we have [tex]$x=1.29 \times 10^{-5}$[/tex] moles of acid
Now to reach pH = [tex]$7.8 (\text{ pOH} = 14-7.8 = 6.2)$[/tex], we must have an [tex]$OH^-$[/tex] concentration of
[tex]$[OH^-] = 10^{-pOH}$[/tex]
[tex]$=10^{-6.2}$[/tex]
[tex]$=6.31 \times 10^{-7}$[/tex] moles of base
We must add enough NaOH of 1 M to neutralize the acid calculated above and also add the calculated base.
[tex]$n \ NaOH = 1.29 \times 10^{-5} + 6.31 \times 10^{-7}$[/tex]
[tex]$=1.35 \times 10^{-5}$[/tex] moles
Vol [tex]$NaOH = 1.35 \times 10^{-5} \text{ moles} \times \frac{1000 \ mL}{1 \ mol}$[/tex]
= 0.0135 L
Tris mass [tex]$H^+ = 0.02 \text{ mol} \times 157.6 \ g/mol$[/tex]
= 3.152 g
To prepare the said solution we must mix
-- [tex]$3.152 \ g \text{ TrisH}^+$[/tex]
-- [tex]$0.0135 \ mL \ NaOH \ 1M$[/tex]
-- [tex]$\text{Gauge to 1000 mL with H}_2\text{O}$[/tex]
While performing a neutralization reaction, Jonna added 27.55 mL of 0.144 M H2SO4 to 43.84 mL of 0.316 M KOH. How many moles of OH- are unreacted in the solution after the neutralization is complete?
Answer:
5.916x10⁻³ mol OH⁻
Explanation:
The reaction that takes place is:
H₂SO₄ + 2KOH → K₂SO₄ + 2H₂OFirst we calculate the added moles of each reagent, using the given volumes and concentrations:
H₂SO₄ ⇒ 0.144 M * 27.55 mL = 3.967 mmol H₂SO₄KOH ⇒ 0.316 M * 43.84 mL = 13.85 mmol KOHNow we calculate how many KOH moles reacted with 3.967 mmol H₂SO₄:
3.967 mmol H₂SO₄ * [tex]\frac{2mmolKOH}{1mmolH_2SO_4}[/tex] = 7.934 mmol KOHFinally we calculate how many OH⁻ moles remained after the reaction
13.85 mmol - 7.934 mmol = 5.916 mmol OH⁻5.916 mmol / 1000 = 5.916x10⁻³ mol OH⁻PLS HELP THIS IS DUE IN 10 MINS!
Compare and contrast floods and droughts. Give two examples of how they are the same and two examples of how they are different.
Calculate the speed of a marble that rolls 9 cm in 4 seconds
Answer:
2.25
Explanation:
9/4
Calculate the molarity of 29.25 grams of NaCI in 2.0 liters of solution
Answer:
[NaCl(aq)] = 0.25M
Explanation:
Molarity = moles solute / volume of solution in liters
moles NaCl in 29.25 grams = 29.25g/58g·mol⁻¹ = 0.5043 mole
Molarity = 0.5043 mole NaCl / 2 Liters = 0.2555M ≅ 0.25M (2 sig-figs)
15POINTS I NEED HELP WITH THIS QUESTION PLEASE!
Answer:
12.76 g
Explanation:
Step 1: Write the balanced equation
4 Fes + 7 O₂ ⇒ 2 Fe₂O₃ + 4 SO₂
Step 2: Calculate the moles corresponding to 11.15 g of O₂
The molar mass of O₂ is 32.00 g/mol.
11.15 g × 1 mol/32.00 g = 0.3484 mol
Step 3: Calculate the moles of SO₂ produced from 0.3484 moles of O₂
The molar ratio of O₂ to SO₂ is 7:4.
0.3484 mol O₂ × 4 mol SO₂/7 mol O₂ = 0.1991 mol SO₂
Step 4: Calculate the mass corresponding to 0.1991 moles of SO₂
The molar mass of SO₂ is 64.07 g/mol.
0.1991 mol × 64.07 g/mol = 12.76 g
Please help me thanks
Answer:
an imbalance of positive and negative charges
Explanation:
Answer:
hope it help s answer circle 3
What are the dependent and independent variables? (Picture^^)
Answer:
X axis shows the independent and Y axis shows the dependent.
Explanation:
As the independent variable is always plotted on the X-axis of the graph the Y-axis shows the dependent variable that is affected by the X variables Time is an independent variable and is always shown along the X-axis. Such as the image showed tells about the data of N2O biofuel emissions from 2009-10. Thus this will be plotted along the X-axis and Y-axis will show the amount of nitrogen fertilizer applied.I NEED AWNSER ASAP What forms as a result of the wind's frictional force on water?
deep sea currents that move in a path opposite to the wind currents
surface currents that move in a path similar to the wind currents
surface currents that move in a path opposite to the wind currents
deep sea currents that move in a path similar to the wind currents (the sub is science)
Answer:
2 no. is the answer surface currents that move in a path opposite to the wind currents
Answer:
no.2 is the answer of your question
what is the purpose of ash to soil conditioning.
Answer:
Question: what is the purpose of ash to soil conditioning?
answer: soil conditioner is a product that is added to soil to improve the soils physical qualities, it's usually the fertility of the soil and sometimes the mechanics of the soil. can be used to improve poor soils.
most wood ash contains a good percentage, about 25 percent, of calcium carbonate, which is an ingredient in garden lime. if your soil is highly acidic, with a pH of 5.5 or lower, amending with wood ash can raise the pH of your soil.
You want to decaffeinate your coffee by extracting the caffeine out with dichloromethane (they don't do it that way anymore, but they used to). It's too late to extract the caffeine from the coffee beans, because you've already brewed yourself a 200 mL cup of coffee. Your particular brand of coffee contains 100 mg of caffeine in that 200 mL cup. The partition coefficient of caffeine in dichloromethane/water is 9.0 (it is more soluble in the dichloromethane).
How much caffeine would still be in your 200 mL if you did:_____.
A. One extraction using 200 mL ofdichloromethane
B. Two extractions using 100 mL ofdichloromethan each.
Solution :
Partition coefficient Kd
[tex]$=\frac{\frac{\text{mass of caffeine in } CH_2Cl_2}{\text{volume of } CH_2Cl_2}}{\frac{\text{mass of caffeine in water}}{\text{volume of water}}}$[/tex]
= 9.0
A). 1 x 200 mL extraction :
Let m be the mass of caffeine in the water
Mass of caffeine in [tex]$CH_2Cl_2$[/tex] = 100 - m
[tex]$\frac{\frac{100-m}{200}}{\frac{m}{200}} = 9.0$[/tex]
[tex]$=\frac{100-m}{m} = 9.0$[/tex]
[tex]$= 10 m = 100$[/tex]
m = 10
Mass remaining in coffee = m = 10 mg
B). 2 x 100 mL extraction :
First extraction :
Let [tex]$m_1$[/tex] be the mass of caffeine in the water
Mass of caffeine in [tex]$CH_2Cl_2$[/tex] = [tex]$100-m_1$[/tex]
[tex]$\frac{\frac{100-m_1}{100}}{\frac{m_1}{200}} = 9.0$[/tex]
[tex]$=\frac{100-m_1}{m_1} = 4.5$[/tex]
[tex]$ 5.5 \ m_1 = 100$[/tex]
[tex]$m_1$[/tex] = 18.18
Mass remaining in coffee = [tex]$m_1$[/tex] = 18.18 mg
Second Extraction :
Let [tex]$m_2$[/tex] be the mass of caffeine in the water
Mass of caffeine in [tex]$CH_2Cl_2$[/tex] = [tex]$18.18-m_2$[/tex]
[tex]$\frac{\frac{18.18-m_2}{100}}{\frac{m_2}{200}} = 9.0$[/tex]
[tex]$=\frac{18.18-m_2}{m_2} = 4.5$[/tex]
[tex]$ 5.5 \ m_2 = 18.18$[/tex]
[tex]$m_2$[/tex] = 3.3
Mass remaining in coffee = [tex]$m_2$[/tex] = 3.3 mg
What is the molar mass of PbSO4?
Answer:
=303.2g
Explanation:
molar mass of Pb = 207.2g
atomic mass of S = 32g
atomic mass of O = 16g
Solution
PbSO4
= 207.2 + 32 + 4 (16)
= 239.2 + 64
= 303.2 g
The molar mass of compound lead sulfate is 207.2 g.
Molar mass of a compound or a molecule is defined as the mass of the elements which are present in it.The molar mass is considered to be a bulk quantity not a molecular quantity. It is often an average of the of the masses at many instances.
Molar masses of an element are given as relative atomic masses while that of compounds is the sum of relative atomic masses which are present in the compound.
atomic mass of S = 32g
atomic mass of O = 16g
PbSO₄= 207.2 + 32 + 4 (16)= 239.2 + 64 = 303.2 g.
Learn more about molar mass,here:
https://brainly.com/question/12127540
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3. Explain what would happen to the digestion process if enzymes were not present. SC.6.L.14.5
How many moles of KBr are present in 1000 ml of a 0.02 M KBr solution?
1. .00002
2. 20
3. 50000
4. .02
5. 50
Answer:
4. .02
Explanation:
Hello there!
In this case, since the molarity of a solution is defined as the moles of the solute divided by the volume of the solution, we can see we are given the molarity and volume and are asked to compute moles; thus, we can solve as shown below:
[tex]M=\frac{n}{V}\\\\n=M*V[/tex]
Whereas the volume must be in liters (1 L in this case); in such a way we can plug in the volume and molarity to obtain:
[tex]n=0.02mol/L*1L\\\\n=0.02mol[/tex]
Therefore, the answer is 4. .02 .
Best regards!
What would be the mass in amu of 150 atoms of carbon?
Answer:
Do you mean the periodic table? The atomic mass of carbon is 12 and oxygen is 16.
If I understand you right though, what you’re looking for is what oxygen’s mass would be in a certain unit of measurement with which carbon weighs 150 units.
In regular atomic mass units carbon’s mass is 12 and oxygen’s is 16, so oxygen’s mass is 4/3 times carbon’s mass. In our new unit of measurement where carbon weights 150 units, oxygen would weigh 150 * 4/3 = 200 units.
Describe the process of two neutral atoms forming an ionic bond
oops... sorry... I need to delete this response. I was trying to answer a different question,
help please guys i need it
Answer:
Amplitude
Explanation:
Hope I helped :)
What does the article “Absolute Zero” tell us about what temperature really means?
Answer:
Absolute zero, technically known as zero kelvins, equals −273.15 degrees Celsius, or -459.67 Fahrenheit, and marks the spot on the thermometer where a system reaches its lowest possible energy, or thermal motion. There's a catch, though: absolute zero is impossible to reach.
Explanation:
GIVING 21 POINTS AWAY PLEASE HELP ME WITH BOTH QUESTIONS ASAP!!!!
Lithium and nitrogen react to produce lithium nitride:
6Li (s) + N2 (g) = 2Li3N (s)
How many moles of lithium nitride are produced when 0.400 mol lithium are used in this reaction?
a. 1.28 mol
b. 0.133 mol
c. 0.800 mol
d. 0.0667 mol
Answer:
B : 0.133 M
Explanation:
moles Li3N3 = 0.4 mol Li x (2 moles Li3N/6 moles Li) = 0.133 M
HELP ME
Elements in a vertical column on the Periodic Table have similar properties and are all members of the same
of elements.
А
molecule
B
phase
С
atom
D
group
Answer:
D group
................
Which resulted from the study of chemistry?
Answer:
I'm confused I think you're suppose to put a picture if you want someone to answer your question just saying.
Explanation:
Answer:
The understanding of the earth, air, fire, and water as the basic components of matter.
Explanation:
Which postmortem parameter is fixed by 8 hours?
1)cloudiness of the eyes
2)rigor mortis
3)livor mortis
4)putrefaction
helppppppppppppppppp
Answer:
b
Explanation:
A certain protein transports a sodium ion from the inside of the cell membrane to the outside using active transport. Which of the following must be true? A. There is no change in concentration before or after transport. B. The transport process did not use chemical energy. C. After transport, the concentration of protein in the cell decreases. D. After transport, the concentration of sodium is lower inside the cell.
Which element best conducts electricity?
argon
copper
nitrogen
oxygen
Answer:
I think it is copper
Explanation:
.........................
Answer:
copper
Explanation:
What is chemistry
What is the bond type in CaO
Answer:
Ionic bond
CaO is an ionic bond. Two-element compounds are usually ionic when one element is a metal and the other is a non-metal. It is made up of one metal ion/cation(Ca^2+) and an non-metal ion/anion(O^2-).
How do the polar easterlies and the jet stream work together to affect the
weather in the United States?
Answer:
they can carry cold arctic air, producing snow and freezing weather.
Explanation:
-w- hope it helps
Name the functional group in the
following molecule:
HSCH2CH3
A. alkane
B. amide
C. thiol
D. alkyl halide
Answer:
C. thiol
Explanation:
Answer:
it's C thiol I just took the test
hope this helps
have a good day :)
Explanation:
Elizabeth REALLY didn’t study, and she also wrote the formula for dicarbon tetrafluoride as “C2F5”. Describe why her answer is incorrect.
Answer:
correct formula: C2F4
Explanation:
tetra means 4. There are 2 C and 4 F in dicarbon tetrafluoride.