Answer:
pH = 2.21
Explanation:
Hello there!
In this case, according to the reaction between NaF and HCl as the latter is added to the buffer:
[tex]NaF+HCl\rightarrow NaCl+HF[/tex]
It is possible for us to see how more HF is formed as HCl is added and therefore, the capacity of this HF/NaF-buffer is diminished as it turns acid. Therefore, it turns out feasible for us to calculate the consumed moles of NaF and the produced moles of HF due to the change in moles induced by HCl:
[tex]n_{HF}^{new}=0.300mol+0.150mol=0.450mol\\\\n_{NaF}^{new}=0.200mol-0.150mol=0.050mol[/tex]
Next, we calculate the resulting concentrations to further apply the Henderson-Hasselbach equation:
[tex][HF]=\frac{0.450mol}{1.0L} =0.450M[/tex]
[tex][NaF]=\frac{0.050mol}{1.0L} =0.050M[/tex]
Now, calculated the pKa of HF:
[tex]pKa=-log(6.8x10^{-4})=3.17[/tex]
We can proceed to the HH equation:
[tex]pH=pKa+log(\frac{[NaF]}{[HF]} )\\\\pH=3.17+log(\frac{0.05M}{0.45M} )\\\\pH=2.21[/tex]
Best regards!
pH is the measure of the hydrogen or hydronium ion concentration in an aqueous solution. The pH of the buffer made with HF and NaF is 2.21.
What is pH?pH is the measure of the acidic or the basic content in a solution that can be given by the hydrogen or the hydroxide concentration.
The reaction can be shown as,
[tex]\rm NaF + HCl \rightarrow NaCl + HF[/tex]
New moles of HF is 0.300 + 0.150 = 0.450 moles and new moles of NaF is 0.200 - 0.150 = 0.050 moles.
The concentration is calculated by the Henderson-Hasselbach equation:
[tex]\rm [HF] = \dfrac{0.450 \;\rm mol}{1.0 \;\rm L} = 0.450 \;\rm M[/tex]
And,
[tex]\rm [NaF] = \dfrac{0.050\;\rm mol}{1.0 \;\rm L} = 0.050\;\rm M[/tex]
pKa of hydrogen fluoride is calculated as:
[tex]\rm pKa = - log (6.8 \times 10^{-4}) = 3.17[/tex]
The pH from the pKa can be calculated as:
[tex]\begin{aligned}\rm pH &=\rm pKa + log (\dfrac{[NaF]}{[HF]})\\\\&= 3.17 + \rm log (\dfrac{0.05}{0.45})\\\\&= 2.21\end{aligned}[/tex]
Therefore, the pH is 2.21.
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what is global warming
HELP!!! WILL GIVE BRAINLYEST!!!!!! Record the Gas concentration associated with each of these time periods. (Note: ppm= parts per million)
Answer:
Explanation:
u need to go to the Greenhouse Effect Simulation (link is in ur Q).
open it and select the Greenhouse effect tab. Note that the concentration of various atmospheric gases during past eras can be determined by looking at gases trapped in ancient ice, such as that found in Antarctica.
On the right hand side panel of the simulation, under “Atmosphere during,” you can select Today, 1750, and Ice Age as historic time periods.
run simulations n collect the gas composition data.
Answer:
Explanation:
The question provides a link to the Greenhouse Effect Simulation. Results are from that:
Time Period H2O %RH CO2 ppm CH4 ppm N2O ppm
Today 58F 70% 338ppm 1843ppm 0.317ppm
1750 58F 70% 280ppm 0.730ppm 0.270ppm
Ice Age 36F ? 180ppm 380ppm 0.215ppm
what is the definition of critical thinking from the book ?
Answer:
Critical thinking is the intellectually disciplined process of actively and skillfully conceptualizing, applying, analyzing.
Explanation:
What molecules are affected by injury to the pancreas?
Answer:
Causative/sensitizing factors of pancreatic injury include refluxed bile acids, alcohol, and pH. They largely mediate downstream events such as elevated intracellular Ca2+ via influx through TRPC3 channels and release from IP3 and ryanodine-sensitive Ca2+ stores.
Explanation:
yield for this reaction?
Reaction: N2(g) + 3 H2(g) → 2 NH3 (g)
Answer:
Yes, yield.
Explanation:
N2(g) + 3 H2(g) → 2 NH3 (g) balanced equation
First, find limiting reactant:
Moles H2 = 1.83 g x 1 mole/2 g = 0.915 moles H2
Moles N2 = 9.84 g N2 x 1 mole/28 g = 0.351 moles N2
The mole ratio of H2: N2 is 3:1, so H2 is limiting (0.915 is less than 3 x 0.351)
Theoretical yield of NH3 = 0.915 mol H2 x 2 mol NH3/3 mol H2 = 0.61 moles NH3
The healthiest foods are low in nutrients such as _______ and _______, and high in nutrients such as _______ and _______.
Answer:
Explanation:
The healthiest foods are low in nutrients such as sodium and fats, and high in nutrients such as proteins and fiber.
Name the following base: NaOH
Answer:
Arrhenius Base
Explanation:
"NaOH is an Arrhenius base because it dissociates in water to give the hydroxide (OH-) and sodium (Na+) ions. An Arrhenius acid is therefore any substance that ionizes when it dissolves in water to give the H+, or hydrogen, ion. ... Acids provide the H+ ion; bases provide the OH- ion; and these ions combine to form water."
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Hope I Helped, Feel free to ask any questions to clarify :)
Have a great day!
More Love, More Peace, Less Hate.
-Aadi x
3. An area where a particular plant has thrived for 50 million years suffers a
100-year-long drought. What evidence of the drought might be found in the fossil
record?
A. Fossils of the plant are abundant right up until the present day.
B. Fossils of the plant appear in recent rock layers but not in older ones.
C. Fossils of the plant are present in older rocks but disappear at a point in the
fossil record
D. It is impossible for the fossil record to show evidence of the drought.
Answer:
Fossils of the plant are abundant right up until the present day. Fossils of the plant appear in recent rock layers but not in older ones.
Explanation:
yay
How many kilojoules are needed to convert 77.5 grams of ice at -8.00°C to water at 95.0°C?
Ahh, Thank you!!! ( ;-;)
Metals are considered to be ___________________ because they let electricity flow.
Group of answer choices
conductors
circuits
currents
insulators
Answer:
conductors
Explanation:
Because they consist of lattice of atoms with free electrons and these free electrons allows current to flow through.
Two reactant particles collide with proper orientation. The collision will be
effective if the particles have
(A) sufficient potential energy
(B) high activation energy
(C) high ionization energy
(D) sufficient kinetic energy
And explain why
Answer: D) Sufficient kinetic energy
Explanation:
WILL MARK BRAINLEST
Explain one way that you could lower the amount of trash that your family produces. Be specific in your example. Explain how it will actually lead to a lower amount of trash
Consider the sugar below.
CH2OH
О
CH2OH
Н
Н
Н
ОН Н
о
ОН
НО
т
ОН Н
Н
ОН
Т-
Н
Н
ОН
Which term best describes this sugar?
disaccharide
monosaccharide
polysaccharide
X saccharide
why is science so disgusting?
Which property of a substance determines whether the substance is a liquid or a solid at room temperature?
a) melting point
b) flexibility
c) solubility
d) conductivity
Answer:
a) melting point
How many atoms of each element are present in methane
and propane based on their chemical formulas
Answer:
Methane has one atom of carbon and four atoms of hydrogen.
Propane has three carbon atoms and eight atoms of hydrogen.
Water vapor is not usually seen.
Answer:
True
Explanation:
Water vapor is totally invisible.
Without it, there would be no clouds or rain or snow, since all of these require water vapor in order to form. All of the water vapor that evaporates from the surface of the Earth eventually returns as precipitation - rain or snow.
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Match each scientist to their discovery regarding the atom
Thomson
Electrons have a charge of -1.
Rutherford
Atoms are indivisible
Millikan
Atoms have a positive nucleus
Dalton
Atoms contain electrons.
Answer:
Thomson--atoms cotain electron
Ernest Rutherford--atoms have a positive nucleus
R.A Millikan--electrons have Q=-1
Dalton--atoms are indivisible
Millikan---> Electrons have a charge of -1
Rutherford ---> Atoms have a positive nucleus
Thomson -----> Atoms contain electrons
Dalton --------> Atoms are indivisible
The atomic theory went through several modifications and different scientists proposed various models of the atom until our present conception of the atom was developed.
The atom was first defined as the smallest indivisible particle of a substance. This idea of "indivisibility" of the atom stems from Dalton's theory.
The fact that atoms were composed of negatively charged electrons was proven by the experiments of J.J Thompson using the cathode ray tube. Millikan's charge to mass experiment showed that the electron has a charge of -1.
Rutherford, in his famous gold foil experiment showed that atoms were composed of a positively charged nucleus.
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Describe the different energy levels of electrons in an atom.
Answer:
Explanation:
If it is at a higher energy level, it is said to be excited, or any electrons that have higher energy than the ground state are excited. They are then called degenerate energy levels.
Europe and United States use geothermal power extensively.
True
False
Answer:
True
Explanation:
US. With an installed capacity of 3,639MW in 2018, the US is the leading producer of geothermal energy across the world, producing 16.7 billion kilowatt hours (kWh) of geothermal energy throughout the year. More recently, extensive direct heat utilization projects have been undertaken in many European countries, and electric power developed extensively in Italy and Iceland. Geothermal heat pumps became extensively used in Austria, Switzerland, Germany and Sweden (Antice, Miklos and Sanner, Burkhard, 2007).
An unknown amount of Al203 decomposed producing 215 g of solid aluminum. 2Al2O3=4Al+3O2 How many grams of oxygen gas should be produced
Answer:
191.11 grams of oxygen gas should be produced.
Explanation:
The balanced reaction is:
2 Al₂O₃ → 4 Al + 3 O₂
By stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:
Al₂O₃: 2 molesAl: 4 molesO₂: 3 molesBeing the molar mass of each compound:
Al₂O₃: 102 g/moleAl: 27 g/moleO₂: 32 g/moleBy reaction stoichiometry, the following mass quantities of each compound participate in the reaction:
Al₂O₃: 2 moles* 102 g/mole= 204 gramsAl: 4 moles* 27 g/mole= 108 gramsO₂: 3 moles* 32 g/mole= 96 gramsThen you can apply the following rule of three: if by stoichiometry 108 grams of aluminum are produced along with 96 grams of oxygen, 215 grams of aluminum are produced along with how much mass of oxygen?
[tex]mass of oxygen=\frac{215 grams of aluminum*96 grams of oxygen}{108grams of aluminum}[/tex]
mass of oxygen= 191.11 grams
191.11 grams of oxygen gas should be produced.
How many moles of C6H12O6 does 8.2 x 1023 molecules represent
Answer:
i.e. mass of 1 mole of glucose, C6H12O6 = (6 × 12.01 + 12 × 1.01 + 6 × 16.00) g = 180.18 g (using atomic weight data to 2 decimals) 1 mole of carbon atoms weighs 12.01 g and there are 6 moles of C atoms in 1 mole of glucose, so the mass of carbon in 1 mole of glucose = 6 × 12.01 g = 72.06 g.
infrared in __________controls
I will mark briniest to the one who is correct, also its fill in the blank I wasnt paying attention in school
Answer:
remote
Explanation:
i hope it helps
Absorption occurs when light waves strike a medium and are neither reflected nor refracted, nor are they allowed to ___________
Answer:
When light waves strike a medium and are neither reflected or refracted, nor are they allowed to pass through.
Explanation:
A gas is most likely to change the liquid phase in the pressure of the gas
Answer: if pressure rises in closed vessel and temperature is low enough,
Gas may condense to liquid state
Typically, this happens when we raise the pressure at room temperature, but there are other situations that aren't covered, including lowering the temperature at room pressure.
What is temperature?Temperature is defined as a measurement of an object or substance's warmth or coldness in relation to a standard value. As opposed to extensive characteristics, like mass or volume, temperature is referred to as an intense property—one that is independent of the quantity of matter being considered—along with pressure, density, and other comparable properties.
If the temperature is low enough and pressure rises in a closed vessel, A gas can turn into a liquid form.
Thus, typically, this happens when we raise the pressure at room temperature, but there are other situations that aren't covered, including lowering the temperature at room pressure.
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Which of the below elements will most likely form an Covalent Bond?
Answer:
You didnt put a link to the picture...
Explanation:
HURRY!! WILL GIVE BRAINLIEST ANSWER!!
1. When aqueous solutions of lead(II) nitrate (Pb(NO3)2) and sulfuric acid
(H2SO4) react, lead(II) sulfate forms as a precipitate. Identify the spectator
ions and write a balanced net ionic equation for this reaction.
The ions Pb2+ and SO42- combine to form the precipitate.
Which two ions are spectator ions?
The net ionic reaction is Pb2+ + SO42...
The spectator ions would be the ions that don't comprise the precipitate in this reaction. You have four ionic species here: Pb²⁺, NO₃⁻, H⁺, and SO₄²⁻. Since Pb²⁺ and SO₄²⁻ combine, as you are told, to form the precipitate, that leaves H⁺ and NO₃⁻ (or, in normal text, H+ and NO3-) to be the spectator ions.
Edit: NO3- might be interpreted ambiguously since it's not immediately clear that the NO3 is a polyatomic ion with a -1 charge and not an NO compound with a 3- charge, so it should be written as [NO3]- or (NO3)-.
The net ionic reaction shows the reaction without the spectator ions. In this case, that would be: Pb²⁺(aq) + SO₄²⁻(aq) → PbSO₄(s).
Which of the following will form a metallic bond with a metal?
a
another metal
b
none of the other choices
c
semimetal
d
a nonmetal
Select the correct answer.
Which statement best describes how chemical equations demonstrate conservation of mass?
A.
The number of reactants is the same as the number of products.
B.
The compounds are the same on each side of the reaction.
C.
The number of atoms of each element is the same on each side of the equation.
D.
The state of matter is the same on each side of the equation.
"C" is correct.
The Law of Conservation of Mass states that matter can be neither created nor destroyed. This is evident in chemical equations as you will always start and end with the same amount of atoms of every element. They are all still there; they have just been rearranged.
Answer: C) The number of atoms of each element is the same on each side of the equation.
Explanation: Mass cannot be created nor destroyed.
pls show your work will mark brainliest
Answer:
0.047 moles
Explanation:
From the question,
Applying
PV = nRT............. Equation 1
Where P = Pressure of CH₄ gas, V = Volume of CH₄ gas, n = number of moles of CH₄ gas, R = Molar gas constant.
make n the subject of the equation
n = PV/RT............. Equation 2
Given: P = 660 torr = (660×0.00131579) atm = 0.868 atm, V = 1300 mL = (1300/1000) L = 1.3 L, T = 20 °C = (20+273) K = 293 K
Constant: R = 0.082 atm.dm³/K.mol
Substitute these values into equation 2
n = (0.868×1.3)/(0.082×293)
n = 1.1284/24.026
n = 0.047 mole
