Consider the sodium borohydride reduction of camphor to isoborneol. A reaction was performed in which 1.000 g of camphor was reduced by an excess of sodium borohydride to make 0.661 g of isoborneol. Calculate the theoretical yield and percent yield for this reaction.

Answers

Answer 1

Answer:

m = 1.0164 g

% = 65.03%

Explanation:

First of all, we need to write the chemical reaction that is taking place here. We have the camphor being reduced to isoborneol:

C₁₀H₁₆O + NaBH₄ -----------> C₁₀H₁₈O + NaBH₂

We have a 1:1 mole ratio between Camphor and isoborneol, so, the moles of the camphor will be the same moles produced of isoborneol.

To get the theorical yield we need to calculate the theorical moles produced of isoborneol, then, the mass and compare it to the given mass. In that way we will get the %yield.

The Molar mass of camphor and isoborneol are:

MM C₁₀H₁₆O = (16*1) + (12*10) + 16 = 152 g/mol

MM C₁₀H₁₈O = (18*1) + (12*10) + 16 = 154 g/mol

The moles of camphor will be:

molesC₁₀H₁₆O = 1 / 152 = 0.0066 moles

The mass produced then of isoborneol should be:

mC₁₀H₁₈O = 0.0066 * 154

mC₁₀H₁₈O = 1.0164 g

Now, the %yield would be:

% = (0.661 / 1.0164) * 100

% = 65.03%

Hope this helps


Related Questions

Convert 0.00353 m to its equivalent in picometers.

Answers

Answer:

[tex] 3530000000 \: pm[/tex]

Explanation:

[tex]0.00353 \: m \\ \\ = 3.53 \times {10}^{ - 3} \: m \\ \\ = 3.53 \times {10}^{ - 3} \times {10}^{12} \\ \\ = 3.53 \times {10}^{ - 3 +12} \\ \\ = 3.53 \times {10}^{9} \: pm\\\\= 3530000000 \:pm[/tex]

can someone help me?​

Answers

Answer:

Itz 4 and watch the superbowl please.

Explanation:

Liquid A and liquid B form a solution that behaves ideally according to Raoult's law. The vapor pressures of the pure substances A and B are 218 torr and 135 torr, respectively. Determine the vapor pressure over the solution if 1.28 moles of liquid A is added to 5.30 moles of liquid B. 1. 42.4 torr 2. 151 torr 3. 188 torr 4. 202 torr 5. 760 torr

Answers

Answer:

Vapor pressure of solution → 151.1 Torr

Option 2.

Explanation:

Raoult's Law is relationed to colligative property about vapor pressure. A determined solute, can make, the vapor pressure of solution decreases.

ΔP = P° . Xm

where Xm is the mole fraction of solute, P° (vapor pressure of pure solvent)

and ΔP = Vapor pressure of pure solvent - Vapor pressure of solution.

In order to determine the vapor pressure of solution, we need to determine, the vapor pressure of B and A in the solution

B's pressure = P° B . Xm

When we add A to B, A works as the solute and B, as the solvent.

Vapor pressure of pure B is 135 torr. (P° B)

In order to determine, the Xm, we use the moles of A and B

Xm = 5.3 mol of B / (1.28 + 5.3) → 0.806

B's pressure = 135 Torr . 0.806 → 108.81 Torr

If mole fraction of B is 0.806, mole fraction for A (solute) will be (1 - 0.806)

A's pressure = 218 Torr . 0.194 → 42.3 Torr

Vapor pressure of solution is sum of vapor pressures of solute + solvent.

Vapor pressure of solution = 42.3 Torr + 108.81 Torr → 151.1 Torr

A thermometer reads -111.1 °F. What is the temperature in °C?

Answers

The temperature is -79.5
To find C, the formula is
K-273.15=C

A
regulation
NBA
basketball
has
a
surface
area
of 283 square inches
.
What
is
the
surface
area
of
this
basketball
in Square Centimeters
?

Answers

Answer:

1.83 × 10³ cm²

Explanation:

Step 1: Given data

Surface area of a NBA basketball (A): 283 in²

Step 2: Convert "A" from square inches to square centimeters

In order to convert "A" from in² to cm², we need a conversion factor. In this case, we will use the conversion factor 1 in = 2.54 cm. Since "in" is raised to the power of 2, we will have to raise the conversion factor to the power of 2 as well.

283 in² × (2.54cm/1 in)² = 1.83 × 10³ cm²

ANSWER ASAP
If the hydrogen atom emits red, blue-green, blue, and violet light, how many energy levels does it have in the visible region of the spectrum?
A. 3
B. 4
C. 5
D. 6

Answers

Answers:

Option B. 4.

Explanation:

The visible spectrum of light emitted by a sample of active or excited hydrogen atoms splits into four wavelengths that are basically four distinct levels of energy in the visible region of the spectrum. There four different wavelengths are 410 nm, 434 nm, 486 nm, and 656 nm. These show for colors according to the spectrum and wavelength violet, blue, green, and red, where 656 nm wavelength is most intense on the spectrum.

The hydrogen atom has four energy levels in the visible region of the spectrum. Therefore, option (B) is correct.

What is the electromagnetic spectrum?

The electromagnetic spectrum can be defined as the range of frequencies of electromagnetic radiation and their respective photon energies and wavelengths.

The electromagnetic spectrum has electromagnetic waves with frequencies ranging from one Hz to above 1025 Hz, corresponding to wavelengths. This frequency range is divided into separate bands: radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays.

Each band has different characteristics, such as interacting with matter, and its practical applications.  When a hydrogen atom emits a different color represents the energy of a different energy level in the visible region of the spectrum.

Therefore, the four colors red, blue-green, blue, and violet light emitted by a hydrogen atom, are of four energy levels in the visible region of the electromagnetic spectrum.

Learn more about electromagnetic spectrum, here:
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All of the following can reduce the risk of heart attacks except which one?

A. Regular exercise

B. Sleep deprivation

C. Low dose apirin

D. Diabetes control

Answers

the answer is B i believe

How many moles of CO2 are there in 2.55 x 10

18

molecules of CO2?

Answers

Answer: There are [tex]4.23\times 10^{-6}moles[/tex]  of [tex]CO_2[/tex]

Explanation:

According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.

To calculate the moles, we use the equation:

[tex]\text{Number of moles}=\frac{\text{Given molecules}}{\text {Avogadros number}}[/tex]

[tex]\text{Number of moles}=\frac{2.55\times 10^{18}}{6.023\times 10^{23}}=0.423\times 10^{-5}moles[/tex]

Thus there are [tex]4.23\times 10^{-6}moles[/tex]  of [tex]CO_2[/tex]

How many sulfur atoms would be present in 41.8 moles of
sulfur?
a
4.18 x 1025 S atoms
b 2.52 x 1025 S atoms
с
1.44 x 1025 S atoms
d
6.94 X 1029 S atoms

Answers

Answer: 2.52*10^25

Explanation:

6.02214076*10^23 in 1 mole

According to Avogadro's number, there are  2.52 x 10²⁵ sulfur atoms present in 41.8 moles of sulfur.

What is Avogadro's number?

Avogadro's number is defined as a proportionality factor which relates number of constituent particles with the amount of substance which is present in the sample.

It has a SI unit of reciprocal mole whose numeric value is expressed in reciprocal mole which is a dimensionless number and is called as Avogadro's constant.It relates the volume of a substance with it's average volume occupied by one of it's particles .

According to the definitions, Avogadro's number depend on determined value of mass of one atom of those elements.It bridges the gap between macroscopic and microscopic world by relating amount of substance with number of particles.

Number of atoms can be calculated using Avogadro's number as follows: mass/molar mass×Avogadro's number.Mass/molar mass is nothing but number of moles .

Therefore, number of atoms=41.8×6.023×10²³=2.52×10²⁵ sulfur atoms.

Thus, there are 2.52 x 10²⁵ sulfur atoms present in 41.8 moles of sulfur.

Learn more about Avogadro's number,here:

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One mole of a metallic oxide reacts with one mole of hydrogen to produce two moles of the pure metal
and one mole of water. 5.00 g of the metallic oxide produces 2.32 g of the metal. What is the metallic
oxide? (Use molar masses)

Answers

Answer:

The metallic oxide is Li₂O

Explanation:

Let the metallic oxide be M₂O

Thus;

M₂O + H₂ = 2M + H₂O

Molar mass of M₂O = (2x + 16)

We assumed Molar mass of M to be x.

We are told that 5.00 g of the metallic oxide produces 2.32 g of the metal.

By proportion, we can write the following;

5g of M₂O × (1 mole of M₂O/(2x + 16)) × (2 moles of M/1 mole of M₂O) = 2.32 g of M × 1 mole of M/x g of M

This cancels out to give us;

10/(2x + 16) = 2.32/x

Cross multiply to get;

10x = 2.32(2x + 16)

10x = 4.64x + 37.12

10x - 4.64x = 37.12

5.36x = 37.12

x = 37.12/5.36

x = 6.925 g/mol

The metal with a molar mass closest to this value of x is Lithium which has a molar mass of 6.94 g/mol

Thus the metal is Lithium and as such the metallic oxide is Li₂O

Which of the following involves a reaction in which energy is absorbed?
O A. An instant cold pack
O B. A car's engine
C. A chemical hand-warmer
O D. A campfire

Answers

A chemical hand warmer because you absorb the heat. Brainliest pls lol

After adding 20.0 mL of 5% NaOH solution into the remaining organic layer, followed by mixing and venting, the solution separated into two distinct layers. Match the following:
1. The top layer was the ______________ layer.
2. 9-fluorenone was most soluble in the ____________ layer.
3. Deprotonated chloroanilic acid was most soluble in the _____________ layer.
4. The bottom layer was the __________________ layer.
5. The organic layer was a ________________ colored solution.
6. The aqueous layer turned into a _____________ colored solution.
a. organic
b. aqueous
c. yellow
d. pink

Answers

Answer:

Explanation:

The objective of this experiment is to match the expected result with each of the propositions given after the experiment had been carried out.

1. The top layer was the organic layer. This is because all the organic compounds have lesser density than water except chloroform that will be formed when NaOH is added.

2. 9-fluorenone was most soluble in the organic layer. This is so as a result of its non-polar carbon structure.

3. Deprotonated chloroanilic acid was most soluble in the aqueous layer as a result of the formation of an electrovalent bond with water.

4. The bottom layer was the aqueous layer as a result of the huge amount of water density.

5. The organic layer was a yellow colored solution.

6. The aqueous layer turned into a pink colored solution.

The reform reaction between steam and gaseous methane (CH4) produces "synthesis gas," a mixture of carbon monoxide gas and dihydrogen gas. Synthesis gas is one of the most widely used industrial chemicals, and is the major industrial source of hydrogen. Suppose a chemical engineer studying a new catalyst for the reform reaction finds that 924. liters per second of methane are consumed when the reaction is run at 261.°C and 0.96atm. Calculate the rate at which dihydrogen is being produced.

Answers

Answer:

The answer is "[tex]= 0.078 \ kg \ H_2[/tex]".

Explanation:

calculating the moles in [tex]CH_4 =\frac{PV}{RT}[/tex]

                                                [tex]=\frac{(0.58 \ atm) \times (923 \ L) }{ (0.0821 \frac{L \cdot atm}{K \cdot mol})(232^{\circ} C +273)}\\\\=\frac{(535.34 \ atm \cdot \ L) }{ (0.0821 \frac{L \cdot atm}{K \cdot mol})(505)K}\\\\=\frac{(535.34 \ atm \cdot \ L) }{ (41.4605 \frac{L \cdot atm}{mol})}\\\\= 12.9 \ mol[/tex]

Eqution:

[tex]CH_4 +H_2O \to 3H_2+ CO \ (g)[/tex]

Calculating the amount of [tex]H_2[/tex] produced:

[tex]= 12.9 \ mol CH_4 \times \frac{3 \ mol \ H_2 }{1 \ mol \ CH_4}\times \frac{2.016 g H_2}{1 \ mol \ H_2}\\\\= 78 \ g \ H_2 \\\\= 0.078 \ kg \ H_2[/tex]

So, the amount of dihydrogen produced = [tex]0.078 \frac{kg}{s}[/tex]

Trucks, airplanes, and trains are used to ____________ people and supplies from one place to another. *

Answers

Answer:

Trucks, airplanes, and trains are used to transport people and supplies from one place to another.

Explanation:

Do air particles exert a force when they collide with objects

yes or no

Answers

Answer:

yes

Explanation:

Gas pressure is caused by the force exerted by gas molecules colliding with the surfaces of objects (Figure 5.2. 1). ... In fact, normal air pressure is strong enough to crush a metal container when not balanced by equal pressure from inside the container.

Answer: Yes Gas pressure is caused by the force exerted by gas molecules colliding with the surfaces of objects (Figure 5.2. ... In fact, normal air pressure is strong enough to crush a metal container when not balanced by equal pressure from inside the container

Explanation:

Give an example of a change that would be a chemical change but not a physical change.

Answers

Answer:

digesting food

Explanation:

you dont see it

Answer:

When you mix two substances and it either smokes, bubbles, gets warmer, or created a new substance.


The higher priority has been given for the use of biogas energy in Nepal, give two reasons.

Answers

Answer:

Biogas units provide a cleaner and safer source of energy, enabling rural families to produce their own electricity, heat, and fertilizer. One advantage of these plants is that they can be used in exactly the place they're needed, thereby averting the need for extensive, costly power landlines.

Which of the following methods would best model how the mountains formed?

potential energy
potential energy

kinetic energy
kinetic energy

electrical energy
electrical energy

chemical energy

Answers

Answer:

Potential energy. Kinetic energy can be stored. ... If we drop the object from the shelf or release the spring, that potential energy is converted back into kinetic energy. Kinetic energy can also be transferred from one body to another in a collision, which can be elastic or inelastic.

You buy butter $3.31 a pound one portion of onion compote requires 1.7 oz of butter how much does the butter for one portion cost round to the nearest cent

Answers

Answer:

The butter for one portion cost is $0.35.

Explanation:

If an object gets smaller due to a change in state, what happens to its volume? How will this affect its density?

Answers

Answer:

the volume of a object will go down but the density stays the same

Volume decreases while density stays the same

what is the gulf stream.
a surface current
a deep current
a river
a climate event

Answers

I think it’s a climate event

the pressure of 1 mol of gas is decreased to 0.05 atm 273.k. what happens to the molar volume of the gas under these conditions?

Answers

The molar volume of the gas : V = 447.993 L

Further explanation

Given

n = 1 mol

P = 0.05 atm

T = 273 K

Required

The molar volume

Solution

Ideal gas law :

PV=nRT

V = nRT/P

Input the value :

V = 1 x 0.08205 x 273 / 0.05

V = 447.993 L

1. Fred is walking at 1.7 m/s, he sees a dollar and runs at 2.5 m/s in 1.5 seconds.
What is his acceleration?

Answers

Answer:

Acceleration is the rate of change of velocity. Usually, acceleration means the speed is changing, but not always. When an object moves in a circular path at a constant speed, it is still accelerating, because the direction of its velocity is changing.

Explanation:

It goes with velocity

Menthol is a crystalline substance with a peppermint taste and odor. When 0.533 g of menthol is dissolved in 25.0 g of cyclohexane, the freezing point of the solution is lowered by 2.84 ∘C. Look up the freezing point and f constant for cyclohexane in the Colligative Constants table. Calculate the molar mass of menthol.

Answers

Answer: The molar mass of menthol is 156.15 g/mol

Explanation:

Depression in freezing point is given by:

[tex]\Delta T_f=K_f\times m[/tex]

[tex]\Delta T_f=T_f^0-T_f=2.84^0C[/tex] = Depression in freezing point

[tex]K_f[/tex] = freezing point constant = [tex]20.8^0C/m[/tex]

m= molality

[tex]\Delta T_f=K_f\times \frac{\text{mass of solute}}{\text{molar mass of solute}\times \text{weight of solvent in kg}}[/tex]

Weight of solvent (cyclohexane)= 25.0 g = 0.025 kg  

Molar mass of solute (menthol) = ?

Mass of solute (menthol) = 0.533 g

[tex]2.84^0C=20.8\times \frac{0.533}{xg/mol\times 0.025}[/tex]

[tex]x=156.15g/mol[/tex]

The molar mass of menthol is 156.15 g/mol

The periodic table shows that a carbon atom has six protons. This means
that a carbon atom also has
*
O Six electrons
An atomic mass that equals six
O Six neutrons
O
More protons than electrons

Answers

Answer:

A carbon atom has six protons. This means that a carbon atom also has

a) Six electrons

b) Six neutrons

Explanation:

In which state of matter are the particles at rest (not moving at all)?
none of these
solid
liquid
gas

Answers

Answer:

Solids for sure

particles of solid cant flow.

Answer:

B)Solids

Solids have  tightly packed particles unlike liquids and gases whose particles can move freely but rate of movement is highest in gas while compared to water

the Earth's surface is colder than the air above it, what will happen to the air?

Answers

Answer:

If the earth's surface is cold, warm air above it will lose heat energy to the cold surface below and the now cool air will remain close to the surface. If a damp surface is warmer than the air above it, some water will evaporate, and the air above the surface will be heated.

Explanation:

:)

You buy rice at 0.71 a pound one batch of fried rice requires 9 pounds of rice how much does the rice for one batch cost round to the nearest cent

Answers

$2.13
Step-by-step explanation:
For one batch of fried rice you need 3 pound of rice, so to know the price per batch we need to know how much 3 pounds of rice cost.
The information we have is
Price Pounds
$0.71 ⇒ 1
x ⇒ 3
the x is the cost of 3 pound of rice, which we find by multiplying $0.71 by 3:
x = ($0.71)(3)= $2.13
The cost of 3 pounds of rice is $2.13, so this is how much the cost in rice for one batch of fried rice is.

33) Which is the correct name for the molecule depicted below?

A. 2-isopropyl-2,3,4-trimethylbutane

B. 2-isopropyl-2,3-dimethylpentane

C. 2,3,3,4-tetramethylhexane

D. 1,1,2,2,3-pentamethylpentane

E. None of these choices is correct.

Answers

Answer:

C. 2,3,3,4-tetramethylhexane

Explanation:

Apply: Click Reset. Set m to 1.0 kg, L to 2.0 m, g to 9.8 m/s2, and θ to –40 degrees. What is the maximum velocity of this pendulum? Show your work. (Hint: The exact height of the pendulum is now 0.468 m.)

Answers

Answer:

[tex]3.029\ \text{m/s}[/tex]

Explanation:

m = Mass of pendulum = 1 kg

L = Length of pendulum = 2 m

g = Acceleration due to gravity = [tex]9.8\ \text{m/s}^2[/tex]

h = Height of the pendulum = 0.468 m

[tex]\theta[/tex] = Angle of deflection = [tex]-40^{\circ}[/tex]

[tex]\cos\theta=\dfrac{L-h}{L}\\\Rightarrow h=L-L\cos\theta\\\Rightarrow h=L(1-\cos\theta)\\\Rightarrow h=2(1-\cos(-40))=0.468\ \text{m}[/tex]

The energy balance of the pendulum is as follows

[tex]mgh=\dfrac{1}{2}mv^2\\\Rightarrow v=\sqrt{2gh}\\\Rightarrow v=\sqrt{2\times 9.8\times 0.468}\\\Rightarrow v=3.029\ \text{m/s}[/tex]

The maximum velocity of this pendulum is [tex]3.029\ \text{m/s}[/tex].

Answer:

Max velocity = 3.03 m/s

Explanation:

Mgh = ½ mv2

(1 kg)(9.8 m/s2)(0.468 m) = ½ (1 kg) v2

2 x 4.5864 = ½ v2 x 2

√V2 = √9.1728

V = 3.03 m/s

I hope this helps!

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