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]
Use the solubility rules from the Lab 4 introduction and your knowledge of qualitative separation schemes from the lab to answer the following questions. The qualitative analysis experiment you did is actually an abbreviated version of a much larger analysis scheme in which many different cations are separated and identified. Suppose a mixture contains Ag , K , NH4 , Hg22 , Pb2 , Mg2 , Sr2 , Ba2 , Cu2 , Al3 and Fe3 .
(a) Which of the following ions could you separate, by causing them to precipitate, with the addition of HCl?
Ag+ K+ NH4+
Hg22+ Pb2+ Mg2+
Sr2+ Ba2+ Cu2+
Al3+ Fe3+
(b) After the addition of HCl, the above sample is centrifuged and decanted. Which of the following cations remaining in the supernatant could you separate, by causing them to precipitate, with the addition of H2SO4? (Hint: H2SO4 is a source of sulfate ions. Select all that apply.)
Ag+ K+ NH4+
Hg22+ Pb2+ Mg2+
Sr2+ Ba2+ Cu2+
Al3+ Fe3+
Answer:
a13+a13
Explanation:
In the UNBALANCED chemical reaction for the combustion of acetylene (used in welding torches), determine at standard temperature and pressure, how many liters of
H2O gas are produced if 12 liters of Oxygen gas are completely consumed?
__C2H2 + __O2 —> __CO2 + __H2O
(Please help! Random answers for points will be reported)
Answer:
2 C2H2 + 5 O2 = 4 CO2 + 2 H2O
I've checked this multiple times this should be it
Hydrofluoric acid and Water react to form fluoride anion and hydronium cation, like this HF(aq) + H_2O(l) rightarrow F(aq) + H_3O^+ (aq) At a certain temperature, a chemist finds that a 5.6 L reaction vessel containing an aqueous solution of hydrofluoric acid, water, fluoride anion, and hydronium cation at equilibrium has the following composition: Calculate the value of the equilibrium constant K_C for this reaction. Round your answer to 2 significant digits. K_C =
Answer:
Kc = 1.09x10⁻⁴
Explanation:
HF = 1.62g
H₂O = 516g
F⁻ = 0.163g
H₃O⁺ = 0.110g
To solve this question we need to find the moles of each reactant in order to solve the molar concentration of each reactan and replacing in the Kc expression. For the reaction, the Kc is:
Kc = [H₃O⁺] [F⁻] / [HF]
Because Kc is defined as the ratio between concentrations of products over reactants powered to its reaction coefficient. Pure liquids as water are not taken into account in Kc expression:
[H₃O⁺] = 0.110g * (1mol /19.01g) = 0.00579moles / 5.6L = 1.03x10⁻³M
[F⁻] = 0.163g * (1mol /19.0g) = 0.00858moles / 5.6L = 1.53x10⁻³M
[HF] = 1.62g * (1mol /20g) = 0.081moles / 5.6L = 0.0145M
Kc = [1.03x10⁻³M] [1.53x10⁻³M] / [0.0145M]
Kc = 1.09x10⁻⁴Ammonia can be made by reaction of water with magnesium nitride as shown by the following unbalanced equation: Mg3N2(s) + H2O(l) Mg(OH)2(s) + NH3(g) If this process is 71% efficient, what mass of ammonia can be prepared from 24.5 kg magnesium nitride?
The mass of ammonia prepared from 24.5 kg magnesium nitride, according to the reaction Mg₃N₂(s) + 6H₂O(l) → 3Mg(OH)₂(s) + 2NH₃(g), knowing that the process is 71% efficient is 5.87 kg.
The balanced reaction of production of ammonia is:
Mg₃N₂(s) + 6H₂O(l) → 3Mg(OH)₂(s) + 2NH₃(g) (1)
First, let's find the number of moles of magnesium nitride
[tex] n_{Mg_{3}N_{2}} = \frac{m_{Mg_{3}N_{2}}}{M_{Mg_{3}N_{2}}} [/tex] (2)
Where:
[tex]m_{Mg_{3}N_{2}}[/tex]: is the mass of Mg₃N₂ = 24.5 kg
[tex]M_{Mg_{3}N_{2}}[/tex]: is the molar mass of Mg₃N₂ = 100.9494 g/mol
The number of moles is (eq 2):
[tex] n_{Mg_{3}N_{2}} = \frac{m_{Mg_{3}N_{2}}}{M_{Mg_{3}N_{2}}} = \frac{24500 g}{100.9494 g/mol} = 242.70 \:moles [/tex]
We can calculate the mass of ammonia prepared, knowing that 1 mol of Mg₃N₂ reacts with 6 moles of H₂O to produce 3 moles of Mg(OH)₂ and 2 moles of NH₃ (reaction 1).
[tex]n_{NH_{3}} = \frac{2\: moles\: NH_{3}}{1\: mol\: Mg_{3}N_{2}}*n_{Mg_{3}N_{2} = \frac{2\: moles\: NH_{3}}{1\: mol\: Mg_{3}N_{2}}*242.70 \:moles \:Mg_{3}N_{2} = 485.4 \:moles[/tex]
Then, the mass of NH₃ is:
[tex] m_{NH_{3}} = n_{NH_{3}}*M_{NH_{3}} = 485.4 \:moles*17.031 g/mol = 8266.8 g = 8.27 kg [/tex]
Since the process is 71% efficient, the mass that can be prepared is:
[tex] m = 8.27 kg*0.71 = 5.87 kg [/tex]
Therefore, the mass of ammonia that can be prepared is 5.87 kg.
I hope it helps you!
what is the structure of methane
Answer:
CH4
Explanation:
if it is wrong, i blame my brain
Go to the Phase Changes tab. Select the particular molecule, and set the temperature to the given values by using the stove to increase or decrease the temperature. Increase the pressure of the cylinder by moving the lid of the cylinder down with the help of the finger. The pressure of the cylinder is indicated by the pressure gauge on the top left corner of the simulation. On the right-hand side of the simulation is the phase diagram for the molecule.
As the molecules collide on the walls of the cylinder, the pressure of the cylinder does not remain constant; it fluctuates slightly as indicated by the gauge.
In the phase diagram, observe the red point. When a particular molecule is selected, set the temperature and pressure condition to the required value. Observe the position of the red point on the phase diagram when the pressure reaches approximately near the required value.
Which of the following conditions will result in the formation of a supercritical fluid?
Check all that apply.
1. Oxygen at 100 K and no pressure
2. Argon at 160 K and approximately 6 atm pressure
3. Water at 294 K and approximately 1 atm pressure
4. Neon at 32 K and approximately 1 atm pressure
5. Neon at 50 K and approximately 10 atm pressure
6. Water at 894 K and approximately 20 atm pressure
7. Argon at 100 K and no pressure
8. Oxygen at 194 K and approximately 2 atm pressure
Answer:
2. Argon at 160K and approximately 6 atm pressure
5. Neon at 50K and approximately 10 atm pressure
6. Water at 894 K and approximately 20 atm pressure
8. Oxygen at 194K and approximately 2 atm pressure
Explanation:
Super critical fluid is formed when temperature rises beyond critical point. The state of molecules can be liquid or gas. The pressure should be above the certain level with an introduction of different gases at minimum of 2 atm pressure.
Limiting Reactant
12.0 grams of sodium reacts with 5.00 grams of chlorine. What mass of sodium
chloride could be produced?
Nas) +
Cl2(g) →
NaCls)
(1)
(2)
Identify the limiting reactant.
Determine the amount of sodium chloride produced.
Answer:
(1) Cl₂ is the limiting reactant.
(2) 8.18 g
Explanation:
2Na(s) + Cl₂(g) → 2NaCl(s)First we convert the given masses of reactants into moles, using their respective molar masses:
Na ⇒ 12.0 g ÷ 23 g/mol = 0.522 mol NaCl₂ ⇒ 5.00 g ÷ 70.9 g/mol = 0.070 mol Cl₂0.070 moles of Cl₂ would react completely with (2 * 0.070) 0.14 moles of Na. There are more Na moles than that, so Na is the reactant in excess while Cl₂ is the limiting reactant.
Then we calculate how many moles of NaCl are formed, using the limiting reactant:
0.070 mol Cl₂ * [tex]\frac{2molNaCl}{1molCl_2}[/tex] = 0.14 mol NaClFinally we convert NaCl moles into grams:
0.14 mol NaCl * 58.44 g/mol = 8.18 gPlease someone help me with this!!
Which statement BEST describes why licensed health care workers are held to a higher standard?
A. They agree to ethical standards when they are licensed.
B. They agree to be good role models and always model good habits.
C. They are more involved than the public.
D. They are more educated than most of the public.
Answer:
They agree to ethical standards when they are licensed.
Explanation:
Answer:
C) They agree to ethical standards when they are licensed
Explanation:
Rock is driven underground and changed by heat and pressure. This describes
what?
a. Igneous changing to sedimentary
b. Metamorphic changing to sedimentary
C. Sedimentary changing to metamorphic
d. Sedimentary changing to igneous
Answer:
Explanation:
metamorphic
Help me please tell me and I try to make u brainliest!
Kevin is working on a model that shows the positions of Earth, the Moon, and the Sun during the phases of
the Moon. How should he position them to show a New Moon?
Answer:
Explanation:what’s the answer
Answer: A. With Earth between the Moon and the Sun.
Explanation:
Fill in the blanks. 3NH3
Answer:
3, 9, 3
Explanation:
The coefficient of 3 tells us that there are three molecules (the chemical unit of NH3). Each molecule of ammonia (NH3) is made up of 1 atom of nitrogen bonded to 3 atoms of hydrogen.
Since there are three molecules, we have three times the amount of atoms there are in one molecule.
3 x 1 = 3 nitrogen
3 x 3 = 9 hydrogen
milk milk milk........
Answer:
gimme that chocky milk.....
Explanation:
Answer:
m i l k
Explanation:
A 50.0-mL volume of 0.15 M HBr is titrated with 0.25 M KOH. Calculate the pH after the addition of 13.0 mL of KOH. Express your answer numerically.
Answer:
pH= 1.17
Explanation:
The neutralization reaction between HBr (acid) and KOH (base) is given by the following equation:
HBr(aq) + KOH(aq) → KBr(aq) + H₂O(l)
According to this equation, 1 mol of HBr reacts with 1 mol of KOH. Then, the moles can be expressed as the product between the molarity of the acid/base solution (M) and the volume in liters (V). So, we calculate the moles of acid and base:
Acid:
M(HBr) = 0.15 M = 0.15 mol/L
V(HBr) = 50.0 mL x 1 L/1000 mL = 0.05 L
moles of HBr = M(HBr) x V(HBr) = 0.15 mol/L x 0.05 L = 7.5 x 10⁻³ moles HBr
Base:
M(KOH) = 0.25 M = 0.25 mol/L
V(HBr) = 13.0 mL x 1 L/1000 mL = 0.013 L
moles of HBr = M(HBr) x V(HBr) = 0.25 mol/L x 0.013 L = 3.25 x 10⁻³ moles KOH
Now, we have: 7.5 x 10⁻³ moles HBr > 3.25 x 10⁻³ moles KOH
HBr is a strong acid and KOH is a strong base, so they are completely dissociated in water: the acid produces H⁺ ions and the base produces OH⁻ ions. So, the difference between the moles of HBr and the moles of KOH is equal to the moles of remaining H⁺ ions after neutralization:
moles of H⁺ = 7.5 x 10⁻³ moles HBr - 3.25 x 10⁻³ moles KOH = 4.25 x 10⁻³ moles H⁺
From the definition of pH:
pH = -log [H⁺]
The concentration of H⁺ ions is calculated from the moles of H⁺ divided into the total volume:
total volume = V(HBr) + V(KOH) = 0.05 L + 0.013 L = 0.063 L
[H⁺] = (moles of H⁺)/(total volume) = 4.25 x 10⁻³ moles/0.063 L = 0.067 M
Finally, we calculate the pH after neutralization:
pH = -log [H⁺] = -log (0.067) = 1.17
PLZ HELP URGENT!!!!!
Answer:
A fluke because it is an vertebrae
Explanation:
How many molecules are in 450.0 grams of aluminum fluoride(AIF3)?
Answer:
It would be exactly 5.3586262014272155. But if you were to round it up it would be 5.35.
HELP PLEASE I NEED HELP THANKS I LOVE U
How many moles of potassium nitrate (KNO3) are there in 0.300 L of a 2 molar solution?
Answer:
0.500-Molarity solution
Explanation:
The moles of the compound is given as the number of atomic mass unit in the compound. The moles of potassium nitrate in the solution are 0.6 mol
What is molarity?The molarity is the concentration unit, and it can be defined as the moles of compound present in the liter of solution.
The molarity can be expressed as:
[tex]\rm Molarity=\dfrac{Moles}{Volume(L)}[/tex]
The given potassium nitrate solution has, molarity = 2 M
The volume of the solution is 0.3 L.
Substituting the values for the moles of the compound:
[tex]\rm 2\;M=\dfrac{Moles}{0.3\;L} \\\\Moles=2\;\times\;0.3\;mol\\Moles=0.6\;mol[/tex]
The moles of potassium nitrate in 2 M solution is 0.6 mol.
Learn more about moles, here:
https://brainly.com/question/15209553
What does this even mean? Help please and thank you!
Answer:
T₁ = P₁V₁T₂ / P₂V₂
Explanation:
The combine gas equation is given by:
P₁V₁ / T₁ = P₂V₂ / T₂
Where:
P₁ => is the initial pressure
V₁ => is the initial volume
T₁ => is the initial temperature
P₂ => is the final pressure
V₂ => is the final volume
T₂ => is the final temperature
Finally, we shall make T₁ the subject of the above expression. This can be obtained as follow:
P₁V₁ / T₁ = P₂V₂ / T₂
Cross multiply
T₁P₂V₂ = P₁V₁T₂
Divide both side by P₂V₂
T₁ = P₁V₁T₂ / P₂V₂
Thus, the formula for T₁ is:
T₁ = P₁V₁T₂ / P₂V₂
An empty steel container is filled with 2.0 atm of H₂ and 1.0 atm of F₂. The system is allowed to reach equilibrium according to the reaction below. If Kp = 0.45 for this reaction, what is the equilibrium partial pressure of HF?
The equilibrium partial pressure of HF is 0.55 atm.
The equation of the reaction is;
H2(g) + F2(g) ⇄ 2HF
I 2 1 0
C -x -x +x
E 2 - x 1 - x x
We know that;
pH2 = 2.0 atm
PF2 = 1.0 atm
pHF = ??
Kp = 0.45
So;
Kp = (pHF)^2/pH2. pF2
0.45 = x^2/(2 - x) (1 - x)
0.45 = x^2/x^2 - 3x + 2
0.45(x^2 - 3x + 2) = x^2
0.45x^2 - 1.35x + 0.9 = x^2
0.55 x^2 + 1.35x - 0.9 = 0
x = 0.55 atm
Learn more about equilibrium: https://brainly.com/question/3980297
Which of this is formed when a metal reacts with steam ? *
Carbon dioxide
A Salt
An oxide
A metal hydroxide
Which phrase describes air density?
increases as altitude increases
equals mass divided by volume
pushes molecules in one direction
exerts less pressure as it increases
If you answer I love you
Answer:B equals mass divided by volume
Explanation:I got hacks :)
Answer:
Which phrase describes air density? well b
increases as altitude increases
equals mass divided by volume
pushes molecules in one direction
exerts less pressure as it increases
Explanation:
love you too!!!!!
Which is a form of kinetic energy?
A. gravitational energy
B. chemical energy
C. electrical energy
D. sound energy
Hydrogen can be produced according to the following word equation
=zinc +hydrochloric acid =zinc chloride +hydrogen [zn^+2]
Write a complete balanced chemical equation for this chemical reaction?
Answer:
Zn + 2HCl → ZnCl₂ + H₂
Explanation:
First we write the equation using the molecular formulas instead of words:
Zn + HCl → ZnCl₂ + H₂We know zinc chloride is ZnCl₂ as the problem tells us the oxidation state of zinc in the products is +2, and chloride means Cl⁻¹.
Now we proceed to balance the reaction:
There are 2 Cl atoms and 2 H atoms on the right side, so we add a coefficient of 2 to HCl on the left side:
Zn + 2HCl → ZnCl₂ + H₂What are the details of the chemical structure of methylisothiazolinone (MIT)?
The only three colors of light the human eye can detect are red, green, and blue.
O True
O False
What is the concentration of a 22.35 L solution that contains 9.95 moles of sodium
acetate? Round your answer to the correct number of significant figures.
Answer:
0.445 M
Explanation:
Molarity = moles/Volume
M = 9.95/22.35 = 0.445 M
3. Explain what would happen to the digestion process if enzymes were not present. SC.6.L.14.5
Joan wants to test if salt lowers the temperature at which water boils. In two or more complete sentences, describe the best way for Joan to develop a hypothesis for this situation. Write your answer in the essay box below.
Answer:
Joan's hypothesis should make a prediction about the answer to the question. A hypothesis is just an educated guess on what you think the outcome will be on the experiment. The prediction must be testable and stated in if-then form. For example, a good hypothesis for Joan's experiment could be, I think that 1/2 cup of salt will make the water boil quicker, than water without salt.
Explanation:
Hope it helped!
Lewis dot diagram for the Cs1+ ion
Answer:
[tex]Cs^+[/tex]
Explanation:
Cesium Lewis dot structure would look like this:
·Cs, because it only has one valence electron. But, since it has a plus, that means we lost an electron. So, we have to get rid of the dot and you have:
[tex]Cs^+[/tex]