A lab technician adds 3.50 mL of a 0.00450 M stock solution of barium chloride to a test tube, then adds other solutions so that the total volume is 10.00 mL.
In the absence of reactions, the molarity of barium ions is ______ M in the solution and the molarity of chloride ions is ______ M in solution.
IMPORTANT: Report each answer to 3 significant figures, I made this as a free response fill-in question and the question will be graded credit/no credit. For example, 0.0000123 or 1.23. Do NOT include units as they are already provided for you.
Answer:
[Ba²⁺] = 1.58 × 10⁻³ M
[Cl⁻] = 3.16 × 10⁻³ M.
Explanation:
Step 1: Calculate the molar concentration of BaCl₂
We have 3.50 mL (V₁) of a 0.00450 M (C₁) BaCl₂ solution and we dilute it to a final volume of 10.00 mL (V₂). We can calculate the final concentration of BaCl₂ by using the dilution rule.
C₁ × V₁ = C₂ × V₂
C₂ = C₁ × V₁ / V₂
C₂ = 0.00450 M × 3.50 mL / 10.00 mL = 1.58 × 10⁻³ M
Step 2: Calculate the molar concentrations of the Ba²⁺ and Cl⁻ ions
Let's consider the dissociation of BaCl₂.
BaCl₂(aq) ⇒ Ba²⁺(aq) + 2 Cl⁻(aq)
The molar ratio of BaCl₂ to Ba²⁺ is 1:1. The molar concentration of Ba²⁺ is 1/1 × 1.58 × 10⁻³ M = 1.58 × 10⁻³ M.
The molar ratio of BaCl₂ to Cl⁻ is 1:2. The molar concentration of Cl⁻ is 2/1 × 1.58 × 10⁻³ M = 3.16 × 10⁻³ M.
Lesson 17 Conservation of Momentum grade 9 I want the answer.
Answer:
1) 1.5 kg
2) 0.6 kg
Explanation:
[tex](3)(30) = 60m, m = 90/60 = 1.5[/tex] kg
[tex](0.8)(15) = 20m, m = 12/20 = 0.6[/tex] kg
How long will it take a 500-W heater to raise the temperature of 400 g of water from 15.0 °C to 98.0
°C?
Explanation:
E=(98-15)×400×4.2
E=139440J
t=E/P
E=139440/500=278.88s
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Convert a pressure of 250 torr to atm a) 0.266 atm b) 0.279 atm c) 0.329 atm d) 0.297 atm
Answer:
C
Explanation:
1atm=760torr
X=250torr
Cross multiply
760torrX=250torr*atm
Divide both sides by 760torr
X=250torr*atm/760torr
X=0.32895atm
X=0.329atm
Option C is collect
The following data were obtained by gas-liquid chromatography on a 40-cm packed column:
Compound tR, min W, min
Air 1.9 —
Methylcyclohexane 10 0.76
Methylcyclohexene 10.9 0.82
Toluene 13.4 1.06
Calculate:
a. an average number of plates from the data.
b. the standard deviation for the average in (a).
c. an average plate height for the column.
Answer:
a)
For Methylcyclohexane N₁ = 2770
For Methylcyclohexene N₂ = 2827
For Toluene N₃ = 2557
b) the standard deviation for the average in (a) is 143.31
c)
For Methylcyclohexane; H₁ = 0.01444 cm
For Methylcyclohexene; H₂ = 0.01415 cm
For Toluene; H₃ = 0.01564 cm
Explanation:
Given the data in the question;
Gas-liquid chromatography on a 40-cm packed column:
Compound tR, min W, min
Air 1.9 —
Methylcyclohexane 10.0 0.76
Methylcyclohexene 10.9 0.82
Toluene 13.4 1.06
a)
an average number of plates from the data;
To get the Number of plates N, we use the following expression;
N = 16( tR / W )², we use it for Methylcyclohexane, Methylcyclohexene and Toluene
-
For Methylcyclohexane N₁ = 16( 10 / 0.76 )² = 16( 173.13 ) = 2770.08 ≈ 2770
-
For Methylcyclohexene N₂ = 16( 10.9 / 0.82 )² = 16( 176.7 ) = 2827.2 ≈ 2827
-
For Toluene N₃ = 16( 13.4 / 1.06 )² = 16( 159.8078 ) = 2556.9 ≈ 2557
b) standard deviation for the average in (a).
First we get the mean;
Mean N" = ( N₁ + N₂ + N₃ ) / 3 = ( 2770 + 2827 + 2557 ) / 3 = 8154 / 3 = 2718
Next we determine the deviation
d₁² = (N₁ - N")² = (2770 - 2718)² = (52)² = 2704
d₂² = (N₂ - N")² = (2827 - 2718)² = (109)² = 11881
d₃² = (N₃ - N")² = (2557 - 2718)² = (-161)² = 25,921
∴ ∑d²[tex]_i[/tex] = 40506
Standard Deviation S = √( ∑d²[tex]_i[/tex] / ( n-1 ) )
Standard Deviation S = √( 40506 / ( 3-1 )
Standard Deviation S = √( 40506 / 2 )
Standard Deviation S = √( 20253 )
Standard Deviation S = 143.31
Therefore, the standard deviation for the average in (a) is 143.31
c)
an average plate height for the column
Given that; Gas-liquid chromatography on a 40-cm packed column, L = 40 cm
-
For Methylcyclohexane; H₁ = L/N₁ = 40 / 2770 = 0.01444 cm
-
For Methylcyclohexene; H₂ = L/N₂ = 40 / 2827 = 0.01415 cm
-
For Toluene; H₃ = L/N₃ = 40 / 2557 = 0.01564 cm
When liquid water freezes into solid ice in the freezer,
Answer:
What about it? I don't get the question
If 56.8 g of FeCl, are formed, how many grams of Fe reacted?
(Explain or show work plz)
Answer:
the molar mass for Fe and Cl
Sample A: 300 mL of 1M sodium chloride
Sample B: 145 mL of 1.5 M sodium chloride
Which sample contains the larger concentration of sodium chloride?
Answer:
Sample A
Explanation:
Molarity of a solution can be calculated using the formula:
Molarity = number of moles (mol) ÷ volume (vol)
For Sample A:
V = 300ml = 300/1000 = 0.3 L
Molarity = 1M
n = number of moles (mol)
1 = n/0.3
n = 0.3moles
For Sample B:
V = 145 mL = 145/1000 = 0.145L
Molarity = 1.5 M
n = number of moles
1.5 = n/0.145
n = 1.5 × 0.145
n = 0.22 moles
Based on the above results (moles), sample A with 0.3 moles contains the larger concentration of sodium chloride.
Determine how many pennies are in the stack on the left in the photograph at the beginning of this module. Create a conversion factor to calculate how many pennies are in the photo, knowing that there are 12 stacks of pennies.
Answer:
I had the answer
Explanation:
Moles to particles Now suppose you want to determine how many particles of sucrose are ... Driving Question Board Have students revisit the DQB to remind themselves of the Unit and Module questions.
The question is listed in the image attached.
A hot metal plate at 150°C has been placed in air at room temperature. Which event would most likely take place
over the next few minutes?
O Molecules in both the metal and the surrounding air will start moving at lower speeds.
O Molecules in both the metal and the surrounding air will start moving at higher speeds.
O The air molecules that are surrounding the metal will slow down, and the molecules in the metal will speed up.
O The air molecules that are surrounding the metal will speed up, and the molecules in the metal will slow down.
Answer: The event air molecules that are surrounding the metal will speed up, and the molecules in the metal will slow down would most likely take place over the next few minutes.
Explanation:
A process in which heat is evolved is called an exothermic process.
When hot metal plate at [tex]150^{o}C[/tex] is placed in air at room temperature then heat is given off by the metal plate due to which there will occur a decrease in kinetic energy of its molecules.
As a result, molecules in the metal will slow down.
Whereas heat is absorbed by the air molecules from the metal due to which kinetic energy of air molecules will increase.
Thus, we can conclude that the event air molecules that are surrounding the metal will speed up, and the molecules in the metal will slow down would most likely take place over the next few minutes.
How many moles of iron are needed to produce 10 moles of Fe2O3
Answer:
20 moles of Iron are needed
Explanation:
In 1 mole of Iron (III) oxide, Fe₂O₃, there are 2 moles of Iron, Fe. The equation that we can write is:
2 moles Fe = 1 mole Fe₂O₃
To find the moles of iron that are needed to produce 10 moles of Fe₂O₃ we must use this equation as follows:
10 moles of Fe₂O₃ * (2 moles Fe / 1mole Fe₂O₃) =
20 moles of Iron are neededWhich of the following substances dissolves most easily in a non polar solvent?
a. NH3
b. H2O
c. NaCl
d. O2
e. BaSO4
Answer:
its e
Explanation:
What is the molarity of a solution that contains 152 g NaCl in 4.00 L solution?
Answer:
200.0lg
Explanation:
please give a brainliest
I’m confused and I don’t understand this, can someone help?
Wilma- tt
Wilbur- TT
c) 100% chance
d) 100% chance
it has been a while since I've done this so it could be wrong but im pretty sure its correct
Wilbur's family claims it is pure so they have TT
and his wife simply has big eyes so its tt
so the chances of their children having either eye shape is 100%
I'm sorry- im not too good at explaining it ><
What is the mass of 1.2 x 1023 atoms of arsenic?
Answer:
14.93 g
Explanation:
First we convert 1.2 x 10²³ atoms of arsenic (As) into moles, using Avogadro's number:
1.2 x 10²³ atoms ÷ 6.023x10²³ atoms/mol = 0.199 mol AsThen we can calculate the mass of 0.199 moles of arsenic, using its molar mass:
0.199 mol * 74.92 g/mol = 14.93 gThus, 1.2x10²³ atoms of arsenic weigh 14.93 grams.
Magnesium metal reacts with oxygen gas
What is the initial appearance of Magnesium metal?
When Magnesium comes in contact with Oxygen, it reacts with Oxygen causing a layer of Magnesium Oxide on the metal. If Magnesium is burnt, it will cause a bright white light creating Magnesium Oxide.
The initial appearance of Magnesium is a ribbon with a layer of Magnesium Oxide.
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80 POINTS
Batteries, motors, and generators all demonstrate what concept?
Newton's Laws
Wave Speed
Conservation of Energy
Chemical Reactions
The exhaust from car engines spreads throughout our atmosphere and adds to pollution. What is this an example of?
A.
An increase in enthalpy
B.
An increase in thrust
C.
An increase in thermodynamics
D.
An increase in entropy
(D is the correct answer!)
Answer: When exhaust from car engines spreads throughout our atmosphere and adds to pollution then it is an example of increase in entropy.
Explanation:
A degree of randomness in the molecules of a substance is called entropy.
When exhaust from car engines spreads throughout our atmosphere then it means the molecules are moving at a faster speed due to which they spread into the atmosphere rapidly.
This means that the entropy of exhaust is increasing.
Thus, we can conclude that when exhaust from car engines spreads throughout our atmosphere and adds to pollution then it is an example of increase in entropy.
An increase in entropy
A 24.0 gram sample of copper was
ncated from 25.0°C to 500.0°C 43783
of heat were absorbed, what is the
Specific_heat of copper?
Answer:
3.84 J/g°C
Explanation:
Using the formula as follows:
Q = m × c × ∆T
Where;
Q = amount of heat (J)
m = mass of substance
c = specific heat of copper
∆T = change in temperature (°C).
Based on the provided information;
Q = 43783J
m = 24g
∆T = 500°C - 25°C = 475°C
c = ?
Using Q = m × c × ∆T
43783 = 24 × c × 475
43783 = 11400c
c = 43783 ÷ 11400
c = 3.84 J/g°C
Three biologically important diatomic species, either because they promote or inhibit life, are
(a) CO,
(b) NO3 and
(c) CN-.
The first binds to hemoglobin, the second is a chemical messenger, and the third interrupts the respiratory electron transfer chain. Their biochemical action is a reflection of their orbital structure. Deduce their ground state electron configurations.
Answer:
See Explanation
Explanation:
We can write the molecular orbital configuration of molecules in the same way as we write the orbital electron configuration of atoms. The valence electrons in the molecule are filled into molecular orbitals of appropriate energy in accordance to the Aufbau principle.
For CO;
σ2s2, σ*2s2, Π2py2, Π2pz2, σ2px2
For NO;
σ2s2, σ*2s2, Π2px2, Π2py2, σ2pz2, Π*2px1
For CN-;
σ2s2, σ*2s2, Π2px2, Π2py2, σ2pz2
These are the ground state electron configurations of these molecules.
The chemical equation below is unbalanced.
NaOH + H3PO4 -> Na3PO4 + H2O
When the equation is correctly balanced, what will be the coefficient of H2O?
Answer:
3 NaOH (aq) + H3PO4 (aq) → Na3PO4 (aq) + 3 H2O (l)
Explanation:
This is an acid-base reaction (neutralization): NaOH is a base, H3PO4 is an acid.
When the equation is balanced, and the coefficient of H₂O is 3.
To balance the chemical equation:
NaOH + H₃PO₄ ⇒ Na₃PO₄ + H₂O
The number of atoms of each element is the same on both sides of the equation.
Balance the hydrogen atoms. There are three hydrogen atoms on the left side and two hydrogen atoms on the right side. To balance the hydrogen atoms, multiply H₂O by a coefficient of 3:
NaOH + H₃PO₄ ⇒ Na₃PO₄ + 3H₂O
If the oxygen (O) atoms are balanced. There are four oxygen atoms on the right side, but only two oxygen atoms on the left side. To balance the oxygen atoms, we need to multiply NaOH by a coefficient of 2.
To learn more about the chemical equation, follow the link:
https://brainly.com/question/28792948
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How many sigma bond and pi bond are present
Using stoichiometry, you predict that you should be able to use 314.0 g of Al to produce 1551 g of AlCi3. In your lab
exercise you actually produced 1400.0 g of aluminum chloride. What is your % yield for this reaction?
CORRECT ANSWER IS: 90.26% but what are the steps on how to get this answer ?
Answer:
90.26%
Explanation:
From the question given above, the following data were obtained:
Theoretical yield of AlCl₃ = 1551 g
Actual yield of AlCl₃ = 1400 g
Percentage yield =?
The percentage yield of the reaction can be obtained as follow:
Percentage yield = Actual yield / Theoretical yield × 100
Percentage yield = 1400 / 1551 × 100
Percentage yield = 140000 / 1551
Percentage yield = 90.26%
Thus, the percentage yield of the reaction is 90.26%
The enthalpy of solution of NaCl in water is about 3.88 kJ/mol. However, the solubility of NaCl in water is relatively high. Which statement about the entropy of the solution process explains why NaCl dissolves in water even though the process is endothermic?
a. the entropy increases when NaCl dissolves in water
b. the entropy remains the same when NaCl dissolves in water
c. the entropy decreases when NaCl dissolves in water
d. entropy has nothing to do with the solution process
We have that the statement that explains why NaCl dissolves in water even though the process is endothermic the given as,
The entropy increases when NaCl dissolves in water.Option A
HeatGenerally ,Sodium chloride is crystalline salt, when its dissolved is H20 , it dissociates its ion, the ions are scattered through out the solution which results in increased in randomness .
Therefore, the entropy increases when NaCl dissolves in water,
Option A
For more information on Heat visit
https://brainly.com/question/15267055
Partial pressure of oxygen dissolved in blood is 50 mm Hg. That means that:
1. It exerts a force per cm^2 equal to that of a column of mercury with 1 cm^2 base and 50 mm height
2. It would be in equilibrium with gaseous oxygen that is at partial pressure of 50 mm Hg
3. Both (1) and (2)
4. Neither (2) or (2)
Answer:
The answer is "Option 2".
Explanation:
In this question, the balance with a partial 50 mm Hg pressure of gassing oxygen.In this, the base value is given in the cm that is incorrect because it is measured in mm.In this, the partial pressure of gas in the liquid is equal to the pure pressure of the gas.
If the nucleus of an atom
contained 6 protons and 7
neutrons, what would be its
mass
Answer:
13
Explanation:
1 proton/neutron has an atomic mass of 1. We ignore the electrons because they are too small. Protons and Neutrons have the same atomic mass, therefore the answer s 6+7=13
A solution is prepared by dissolving 16.90 g of ordinary sugar (sucrose, C12H22O11, 342.3 g/mol) in 40.90 g of water. Calculate the boiling point of the solution. Sucrose is a nonvolatile nonelectrolyte.
Answer:
Explanation:
The boiling point will increase due to dissolution of sugar in water . Increase in boiling point ΔT
ΔT = Kb x m , where Kb is molal elevation constant water , m is molality of solution
Kb for water = .51°C /m
moles of sugar = 16.90 / 342.3
= .04937 moles
m = moles of sugar / kg of water
= .04937 / .04090
= 1.207
ΔT = Kb x m
= .51 x 1.207
= .62°C .
So , boiling point of water = 100.62°C .
A piece of wood has a mass of 36g and measures 3cm X 6cm X 4cm. What is the density of the wood? Would the piece of wood float or sink in water?
Answer:
Explanation:
The density is
1.1 g c m 3 .
The masses of carbon and hydrogen in samples of four pure hydrocarbons are given above. The hydrocarbon in which sample has the same empirical formula as propene, C3H6
Sample Mass of carbon Mass of hydrogen
A 60g 12g
B 72g 12g
C 84g 10g
D 90g 10g
a. Sample A
b. Sample B
c. Sample C
d. Sample D
Answer:
Sample B
Explanation:
In this case, we need to determine the empirical formula for each sample. The one that match the formula of the propene would be the sample.
Let's do Sample A:
C: 60 g; H: 12 g
1. Calculate moles:
We need the atomic weights of carbon (12 g/mol) and hydrogen (1 g/mol):
C: 60 / 12 = 5
H: 12 / 1 = 12
2. Determine number of atoms in the formula
In this case, we just divide the lowest moles obtained in the previous part, by all the moles:
C: 5 / 5 = 1
H: 12 / 5 = 2.4 or rounded to two
3. Write the empirical formula:
Now, the prior results, represent the number of atoms in the empirical formula for each element, so, we put them with the symbol and the atoms as subscripted:
C₁H₂ = CH₂
Therefore, sample A is not the same as propene.
Sample B:
C: 72 g H: 12 g
Following the same steps, let's determine the empirical formula for this sample
C: 72 / 12 = 6 ---> 6 / 6 = 1
H: 12 / 1 = 12 ----> 12 / 6 = 2
EF: CH₂
Sample C:
C: 84 g H: 10 g
C: 84 / 12 = 7 ----> 7 / 7 = 1
H: 10 / 1 = 10 ----> 10 / 7 = 1.4 or just 1
EF: CH
Sample D
C: 90 g H: 10 g
C: 90 / 12 = 7.5 -----> 7.5 / 7.5 = 1
H: 10 / 1 = 10 -------> 10 / 7.5 = 1.33 or just 1
EF: CH
Neither compound has the same empirical formula as C3H6, but C3H6 is a molecular formula, so, if we just simplify the formula we have:
C3H6 -----> CH₂
Therefore, sample B is the one that match completely. Sample B would be the one.
Hope this helps