Answer:
a) pH = 9.44
b) 25mL of HBr are required.
c) pH = 5.37
d) pH = 9.26
Explanation:
The equilibrium of NH₃ in water occurs as follows:
NH₃(aq) + H₂O(l) ⇄ NH₄⁺(aq) + OH⁻(aq)
Kb = 1.8x10⁻⁵ = [NH₄⁺] [OH⁻] / [NH₃]
The reaction of NH₃ with HBr is:
NH₃ + HBr ⇄ NH₄⁺ + Br⁻
That means when you add X moles of HBr before to reach the equivalence point, the moles are:
Moles NH₃ = Initial moles - moles HBr
Moles NH₄⁺ = Moles HBr
Initial moles NH₃ = 0.050L * (0.05mol / L) = 2.5x10⁻³ moles NH₃
Moles HBr = 0.010L * (0.10mol / L) = 1x10⁻³ moles HBr
Thus, after the reaction:
Moles NH₃ = 1.5x10⁻³moles
Moles NH₄⁺ = 1x10⁻³ moles
Using Henderson-Hasselbalch equation, pH of this solution is:
pOH = pKb + log [NH₄⁺] / [NH₃]
Where pKb is -log Kb = 4.74
And [] could be taken as moles of each compound:
pOH = 4.74 + log [1x10⁻³ moles] / [1.5x10⁻³ moles]
pOH = 4.56
And pH = 14 - 4.56
pH = 9.44b) To reach equivalence point, we need to add 2.5x10⁻³ moles HBr:
2.5x10⁻³ moles HBr * (1L / 0.10mol) = 0.025L = 25mL of HBr are required
c)At equivalence point, you will have just 2.5x10⁻³ moles of NH₄⁺ in 50.0mL + 25mL = 75mL. The molar mass of NH₄⁺ is:
[NH₄⁺] = 2.5x10⁻³mol / 0.075L = 0.0333M
The equilibrium of NH₄⁺ is:
NH₄⁺ ⇄ NH₃ + H⁺
Ka = [NH₃] [H⁺] / [NH₄⁺] = 5.556x10⁻¹⁰
[NH₃] = [H⁺] because both comes from the same equilibrium and [NH₄⁺] = 0.0333M:
[X] [X] / [0.0333M] = 5.556x10⁻¹⁰
[X]² = 1.85x10⁻¹¹M
[X] = [H⁺] = 4.3x10⁻¹¹M
pH = -log [H⁺] = 5.37
d) At midpoint, [NH₃] = [NH₄⁺]. Using H-H equation:
pOH = 4.74 + log [NH₃] / [NH₄⁺]
pOH = 4.74
And pH = 14 - 4.74
pH = 9.26Find and fix each mistake in the following equilibrium constant expressions.
Part A
2H2S(g)?2H2(g)+S2(g)
Keq=[H2][S2][H2S]
a. Keq=[H2S]^2/[H2]2[S2]
b. Keq=[H2S]/[H2][S2]
c. Keq=[H2]^2[S2]/[H2S]^2
Part B
CO(g)+Cl2(g)?COCl2(g)
Keq=[CO][Cl2][COCl2]
a. Keq=[CO][Cl2]^2/[COCl2]^2
b. Keq=[COCl2]/[CO][Cl2]
c. Keq=[COCl2]^2/[CO][Cl2]^2
Answer:
A. c. Keq=[H2]^2[S2]/[H2S]^2
B. b. Keq=[COCl2]/[CO][Cl2]
Explanation:
Hello,
In this case, considering the law of mass action which states that the equilibrium expression is written in terms of the concentration of products divided by the concentration of reactants considering the stoichiometric coefficients as powers we obtain:
A. For the reaction:
[tex]2H_2S(g)\rightleftharpoons 2H_2(g)+S_2(g)[/tex]
The equilibrium expression is:
[tex]Keq=\frac{[H_2]^2[S_2]}{[H_2S]^2}[/tex]
Therefore, answer is c. Keq=[H2]^2[S2]/[H2S]^2.
B. For the reaction:
[tex]CO(g)+Cl_2(g)\rightleftharpoons COCl_2(g)[/tex]
The equilibrium expression is:
[tex]Keq=\frac{[COCl_2]}{[CO][Cl_2]}[/tex]
Therefore, answer is b. Keq=[COCl2]/[CO][Cl2].
Regards.
Explain why or why not it’s necessary for the scientific process to always follow the same route
Answer:
Explanation:
The scientific method describes the processes by which scientists gain knowledge about the world. It's characterized by six key elements: questions, hypotheses, experiments, observations, analyses, and conclusions. These elements are interrelated steps, so they don't always function in the same order.
how are pure carbon, oxygen and hydrogen different from the compound ethanol which contains all three of those elements?
Learn more:
brainly.com/question/19235553
Answer:
Explanation:
https://brainly.com/question/19235553
Methanol, a potential replacement for gasoline as an automotive fuel, can be made from H2 and CO by the reaction
CO(g) + 2H2(g) CH3OH(g)
At 500.0 K, this reaction has Kp = 6.25 x 10-3. Calculate ?
Answer:
[tex]\Delta G=-48.2kJ/mol[/tex]
Explanation:
Hello,
In this case, considering that the relationship between Kp and K is:
[tex]K=\frac{Kp}{RT^{\Delta \nu}}[/tex]
Whereas the change in the number of moles (stoichiometric coefficients) is:
[tex]\Delta \nu=1-2-1=-2[/tex]
The equilibrium constant is:
[tex]K=\frac{6.25x10^{-3}}{(8.314\frac{J}{mol\times K}*500.0K)^{-2}}\\\\K=1.08x10^{5}[/tex]
In such a way, the Gibbs free energy of reaction is:
[tex]\Delta G=-RTln(K)=-8.314\frac{J}{mol\times K}*500.0K*ln(1.08x10^5)\\\\\Delta G=-48.2kJ/mol[/tex]
Regards.
Which one of the following compounds produces a basic solution when dissolved in water? a. Na_2O b. CO_2 c. O_2 d. SO_2 e. OF_2
Answer:
a. Na_2O.
Explanation:
Hello,
In this case, the formation of a basic solution accounts for the formation of a base or hydroxide which contains hydroxide ions. Such hydroxides are formed via the combination reaction between water and a basic oxide which is formed by a metal and oxygen, that is way a. Na_2O forms the basic solution as it forms sodium hydroxide via:
[tex]Na_2O+H_2O\rightarrow 2NaOH[/tex]
Best regards.
If our aim is to make 100% pure alum, how could large chunks be bad?
Answer:
It prevent the solution from making 100% pure alum.
Explanation:
Large chunks could be bad if we make 100% pure alum because the large chunks prevent the production of 100% pure alum so for making 100% pure alum, large chunks will be removed from the solution or process. Alum is a chemical compound having salt of sulfate attached with aluminum in hydrated form i. e. presence of water. It is widely used in vaccines and for the purification of drinking water.
which are made matters
Answer:
Everything you can hold, taste, or smell is made of matter. Matter makes up everything you can see, including clothes, water, food, plants, and animals. It even makes up some things you cannot see, such as air or the smell of perfume.
can anyone please help with this!!
Answer:
2341, last option is the correct choice.
Explanation:
Boiling points of the given compounds are given as:
[tex]CH_4=-161.5\:C^{\circ}\\\\C_4H_{10}=-1\:C^{\circ}\\\\CH_2Cl_2=39.6\:C^{\circ}\\\\H_2O=100\:C^{\circ}[/tex]
Best Regards!
CALCULATE: you need to type/show your work. There is no credit if the work is not show/typed Titanium has five common isotopes: 46Ti (8.00%), mass= 45.953 amu 47 Ti (7.80%), mass= 46.952 amu 48Ti (73.40%), mass= 47.947 amu 49Ti (5.50%), mass= 48.948 amu 50Ti (5.30%), mass = 49.945 amu Calculate the average atomic mass of titanium.
Answer:
47.871 amu
Explanation:
Average atomic mass of an atom is obtained from the sum of the mass of the isotopes multiplicated by its natural abundance.
That means atomic mass of Ti is:
Ti = 45.953*8.00% + 46.952*7.80% + 47.947*73.40% + 48.948*5.50% + 49.945*5.30%
Average atomic mass of Ti:
47.871 amuWhat is the potential energy of the ball when it gets to its maximum height just before falling back to the ground?J
Answer:
9.8 joules
Explanation:
due to acceleration due to gravity
1) How many moles of atoms are in 3.00 g of 13C?2) Based on your answer in Part B, how many electrons are in this amount of 13C?3) Based on your answer in Part B, how many neutrons are in this amount of 13C?
Answer:
1) 1.39 * 10²³ atoms
2) 8.43 * 10²³ electrons
3) 9.73 * 10²³ neutrons
Explanation:
1) 13 g of C-13 contains 6.02 *10²³ atoms
3.00 g of C-13 will contain 6.02 * 10²³ * (3/13) = 1.39 * 10²³ atoms
2) Each atom of C-13 contains 6 electrons
Therefore 3.00 g of C-13 will contain 6 * 1.39 * 10²³ electrons = 8.43 * 10²³ electrons
3) Each atom of C-13 contains 7 neutrons
Therefore, 3.00 g of C-13 will contain 7 * 1.39 * 10²³ neutrons = 9.73 * 10²³ neutrons
g The tolerance of a Class A 50 mL transfer pipet is ±0.05 mL. A student uses an uncalibrated Class A transfer pipet to deliver a total of 150 mL of solution. What is the uncertainty in the delivered 150 mL? Note: tolerance is different from the uncertainty, so it does not follow the propagation formula of errors
Answer:
Uncertainty of tolerance transfer pipet = ± 0.15
Volume of liquid between = 149.85, 150.15
Given:
Size of transfer pipet = 50 ml
Tolerance transfer pipet = ± 0.05 ml
Total transfer = 150 ml
Find:
Uncertainty of tolerance transfer pipet
Computation:
Uncertainty of tolerance transfer pipet = [150 / 50](± 0.05)
Uncertainty of tolerance transfer pipet = [3](± 0.05)
Uncertainty of tolerance transfer pipet = ± 0.15
Volume of liquid between = (150-0.15), (150+0.15)
Volume of liquid between = 149.85, 150.15
A compound is found to contain 46.68 % nitrogen and 53.32 % oxygen by mass. To answer the question, enter the elements in the order presented above. QUESTION 1: The empirical formula for this compound is . QUESTION 2: The molar mass for this compound is 30.01 g/mol. The molecular formula for this compound is
Answer:
Q1: NO
Q2: NO
Explanation:
Step 1: Given data
Percentage by mass of nitrogen: 46.68%
Percentage by mass of oxygen: 53.32%
Step 2: Divide each percentage by the mass of the element
N: 46.68/14.01 = 3.332
O: 53.32/16.00 = 3.332
Step 3: Divide both numbers by the smallest one (in this case is the same)
N: 3.332/3.332 = 1
O: 3.332/3.332 = 1
The empirical formula is NO. Its molar mass is 30.01 g/mol.
Step 4: Calculate "n"
n = molar mass of the molecular formula / molar mass of the empirical formula
n = (30.01 g/mol) / (30.01 g/mol) = 1
Step 5: Determine the molecular formula
We do so by multiplying the empirical formula by "n".
NO × 1 = NO
Glassblower creating sculptures out of glass physical or chemical
Answer:
phsical
Explanation:
it is a phisical cuz your only changing the shape not the chemical structure
You have a 16 g sample of ethanol with a density of 0.7893 g/mL. What volume of ethanol do you have?
Answer:
Density is mass/volume d=m/v so volume = m/d or mass divided by density.
That would be 23 / 0.7893 = 29.1397 or 29.14 mL. Grams cancels out
Explanation:
The volume of ethanol is 20.27 g/ml.
What is volume?The area occupied by a three-dimensional object is its volume. It can be determined using density and mass. Liters are used to measure it. The overall weight of a thing is its mass. M designates it.
The mass per unit volume is known as density. The capital letter D and the symbol rho stand for density. You can figure it out by dividing the mass by the volume.
rho = m / V
rho = density
m = mass
V = volume
Given the mass of the sample of ethanol weighs 16 g
The density of 0.7893 g/mL
Putting the values in the equation
Volume = 16 / 0.7893 = 20.27
Thus, the volume of ethanol is 20.27 g/ml.
To learn more about volume, refer to the link:
https://brainly.com/question/16940422
#SPJ2
(3.605 X 10^-27) + (4.01 X 10^-25)
Answer in scientific notation
A sample of water is measured with a 2 mL volumetric pipet. What volume
measurement should be recorded with the correct number of decimal places?
Answer:
Explanation:
A pipette is used to measure an exact volume of liquid; a pipette can only measure it's exact recommended volume (it can't measure more or less).
Hence, a 2-mL volumetric pipette can only measure 2 ml and would be recorded as 2.00 (ml). This is because simple volumes are usually recorded in two decimal places.
What technique would you use to separate the Drierite from the silicon? *
Answer:
Filtration
Explanation:
Filtration is a separation technique used in the laboratories to separate two elements or compounds by using a filter paper and a beaker.
Drierite is also know as calcium sulphate and silicon is made up of silica.
The filtration equipment are taken to separate these two components. The separation method is used in the second beaker by pouring the mixture through a filtering funnel and using a filter paper. The solid remaining of silicon remains on the filter paper separating the two.
How many electrons are found in an atom of Oyxgen?
10 points
16
O 24
8
Answer:
8 electrons.
Explanation:
On a periodic table, one can see that Oxygen has 8 protons.
The number of protons in a neutral atom will always equal the number of electrons.
Liquids that do not mix can be separated by which technique
A) Filtration
B) Distillation
C) Decantation
D) Evaporation
what would happen if the leopard attacked any one zebra or wildebeest.
Answer:
Lepord would win.
Explanation:
The Wildbeast is just another goat/sheep so its like a lepord fighting one of them so the Lepord would win.
why do oxygen and hydrogen can be kept underwater
Lesson Question: How can you determine the specific heat of a
metal using a calorimeter?
To do this computation for each of the four metals, you needed
several measurements.
v of the metal and the water
- First, you measured the
inside the calorimeter.
the metal and added it to water in the
. Then, you
calorimeter.
12.459
- After heat transferred from the metal to the water, you measured
the
of both materials.
DONE
Intro
No
Answer:
the person above me is correct
Explanation:
Multiply 17.243 × 0.95 = _____
Answer:16.38085
Explanation:Aline the decimals then start multiplying.
2A + 3B--> A2B3 If 3mL of 0.04M A, 4mL of 0.02M B and 3mL of H2O was into a reaction test tube, what are the concentrations of A and B in the test tube.
Answer:
[tex][A]=0.012M[/tex]
[tex][B]=0.008M[/tex]
Explanation:
Hello,
In this case, given the concentration and volume of each reactant, we first compute their moles in the solution:
[tex]n_A=0.003L*0.04mol/L=1.2x10^{-4}mol\\\\n_B=0.004L*0.02mol/L=8x10^{-5}mol[/tex]
Thus, since the total volume is computed given the volume of each reactant as well as the extra water, we have:
[tex]V=0.003L+0.004L+0.003L=0.010L[/tex]
Thus, the concentrations of A and B are:
[tex][A]=\frac{1.2x10^{-4}mol}{0.010L}=0.012M[/tex]
[tex][B]=\frac{8x10^{-5}mol}{0.010L}=0.008M[/tex]
Best regards.
Weak noncovalent interactions:__________ a. do not include ionic interactions b. always involve water. c. can have a large cumulative effect d. combine to form covalent interactions
Answer:
c. can have a large cumulative effect
Explanation:
Noncovalent interactions between molecules are weaker than covalent interactions. Noncovalent interactions between molecules are of various types which include van der Waals forces, hydrogen bonding, and electrostatic interactions or ionic bonding.
van der Waals forces are weak interactions found in all molecules. They include dipole-dipole interactions - formed due to the differences in the electronegativity of atoms - and the London dispersion forces.
Hydrogen Bonds results when electrons are shared between hydrogen and a strongly electronegative atoms like fluorine, nitrogen, oxygen. The hydrogen acquires a partial positive charge while the electronegative atom acquires a partial negative. This results in attraction between hydrogen and neighboring electronegative molecules.
Ionic bonds result due to the attraction between groups with opposite electrical charges, for example in common salt between sodium and chloride ions.
Even though these noncovalent interactions are weak, cumulatively, they exert strong effect. For example, the high boiling point of water and the crystal structure of ice are due to hydrogen bonding.
Which is more dense? A foam ball or a bowling ball?
Please help! Only answer if you know the answer 100%
How much grams are in 4.78 cup
Answer:
1130.89
Explanation:
Answer:
963.648
Explanat:::::::)))))))
5.05 g
Express your answer as an integer.
Answer:5.5
Explanation:
Determine the partial negative charge on the bromine atom in a c−br bond. the bond length is 1.93 å and the bond dipole moment is 1.40 d . express your answer using 3 significant figures. the partial negative charge on the bromine atom = previous answersrequest answer incorrect; try again; 4 attempts remaining provide feedback.
Answer:
The value is [tex]x = 0.151 \ e [/tex]
Explanation:
From the question we are told that
The bond length is [tex]l = 1.93\ \r a = 1.93 *1 *10^{-10} =1.93 *10^{-10}\ m [/tex]
The bond dipole moment is [tex] \mu = 1.40 d = 1.40 * 3.33564 *10^{-30} = 4.6699 *10^{-30} \ C \cdot m[/tex]
Generally the dipole moment is mathematically represented as
[tex]\mu = Q * l[/tex]
Here Q is the partial negative charge on the bromine atom
So
[tex]Q = \frac{\mu}{ l}[/tex]
=> [tex]Q = \frac{4.6699 *10^{-30}}{ 1.93 *10^{-10} }[/tex]
=> [tex]Q = 2.42 *10^{-20} C [/tex]
Generally
1 electronic charge(e) is equivalent to [tex]1.60*10^{-19} C[/tex]
So x electronic charge(e) is equivalent to [tex]Q = 2.42 *10^{-20} C [/tex]
=> [tex]x = \frac{2.42 *10^{-20}}{1.60*10^{-19} }[/tex]
=> [tex]x = 0.151 \ e [/tex]
