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Question 15
We're given the [OH⁻] as 8.34 × 10⁻¹² M. Using the formula pOH = -log[OH⁻], the pOH of this solution would be -log(8.34 × 10⁻¹²) ≈ 11.08.
The pOH is, for lack of a better term, the "opposite" of pH: A pOH of 7 is neutral; a pOH less than 7 is basic; and a pOH greater than 7 is acidic.
This follows from the relation, pH + pOH = 14. In this case, with a pOH of 11.08, our pH would be 14 - 11.08 = 2.92, which is acidic (pH < 7).
Thus, the correct answer choice is B.
An electron confined in a one-dimensional box is observed, at different times, to have energies of 12 eV, 27 eV, and 48 eV. What is the length of the box? 45. | The nucleus of a typical atom
Answer:
[tex]l=3.5*10^{-10}m[/tex]
Explanation:
From the question we are told that:
1st Energy [tex]E_1=12eV=4(3eV)[/tex]
2nd Energy [tex]E_2=27eV=9(3eV)[/tex]
3rd Energy [tex]E_3=48eV=16(3eV)[/tex]
Generally the equation for Energy E for electron in one dimensional box at ground state [tex]E_0[/tex] is mathematically given by
[tex]E_0=\frac{h}{8ml^2}[/tex]
[tex]E_0=\frac{h}{8ml^2}[/tex]
Therefore Length a is mathematically given as
[tex]l=\sqrt{\frac{h^2}{8mE_0} }[/tex]
[tex]l=\sqrt{\frac{(6.625*10^{-34})^2}{8(9.1*19^{-31}{(3eV(1.6*10^{-19}))}}[/tex]
[tex]l=3.5*10^{-10}m[/tex]
7. Which of the following is a proof that light travels in a straight line?
A. Formation of clouds
C. Formation of rainbows
B. Formation of colors
D. Formation of shadow
Answer:
formation of shadow is right
Answer:
correct answer is D
Explanation:
When you see a shadow, it is directly behind the object.
A report for a written communication?
Answer:
It is a document that promotes essential communications, such as communications organizations.
Explanation:
There are several models of written report for communicating. Reports are documents widely used in organizations, whose communication is an essential tool for the correct flow of business. Some of them are written in the form of e-mails, memos, letters, etc.
The reports assist in business communication and must be written in the format and specific subject for the recipient.
The company's need to issue written reports is to assist in the organization of the business, in planning, in decision-making, and in everything that concerns the operationalization of organizational systems.
3.
The color of the powdered form of a mineral is called
O fracture
O cleavage
O luster
O streak
Answer:
D. Streak.
Explanation:
A mineral, in simple terms, can be defined as a solid inorganic substance that occurs in a pure form with a specific crystal structure. A mineral is identified based on its physical properties which include luster, color, streak, crystal shape, etc.
The color of the powdered form of a mineral is called a streak. A streak is a useful property in distinguishing sulfide and oxide minerals. To check the color of a mineral, it is rubbed against the surface of a ceramic streak plate or a piece of unglazed ceramic. In its finely powdered form, a mineral is easy to identify.
Therefore, option D is correct.
One peanut M&M weighs approximately 2.33 g.
A. How many peanut M&Ms are there in 53.768 kg of M&M's?
Answer:
There are 23076 peanut M&M's in 53.768 kg of M&M's.
Explanation:
First we convert 53.768 kg into g:
53.768 kg * 1000 = 53768 gThen we divide the total mass of M&M's by the mass of one peanut M&M, in order to calculate the answer:
53768 g / 2.33 g = 23076So there are 23076 peanut M&M's in 53.768 kg of M&M's.
23. Forces accelerate objects. Newton's second law state that force equals ______times?
Answer:
F = ma, or force is equal to mass times acceleration.
Name (3) ways an animal can use energy from food?
Answer:
The food chain begins with the sun: plants get their energy by photosynthesizing sunlight into energy, and then herbivores eat those plants to get their energy. Carnivores who then eat the herbivores are getting that sunlight passed along from sun to plant to herbivore to carnivore.
Use the drop-down menus to match the name and structure for the following cycloalkanes. A five-sided polygon. A square. A five-sided polygon with one line extending from a point. A 6-sided polygon with a line extending from one point to a C H 3.
Answer:
A five-sided polygon.- cyclopentane
A square.- cyclobutane
A five-sided polygon with one line extending from a point.- methylcyclopentane
A 6-sided polygon with a line extending from one point to a C H 3.- methlcyclohexane
Explanation:
The correct options are :
The 5 sided polygon is cyclopentane.The square is a cyclobutane.The 5 sided polygon extends from a point.- methyl cyclopentane.The six-sided polygon CH3 is methylcyclohexane.What are cycloalkanes?Cycloalkane is a cyclic hydrocarbon meaning that the carbon of the molecules is arranged in the form of a ring. These are also saturated and all of the carbon stems make up a ring.
These are monocyclic and made from hydrogen and carbon. One ring structure is named after cyclo. Cyclobutane is columns gases and is available in liquefied gas.
Find out more information about the cycloalkanes.
brainly.com/question/10189586
if energy cannot be created then how did it exist in the first place???
Answer:
Different types of generators are used to create energy. Electrical energy is caused by moving electric charges called electrons. Electricity is a type of energy that comes from electrical energy. ... In power stations, turbines are turned using energy from sources such as heat, wind and moving water.
Explanation:
Joaquin's doctor tested Joaquin's reflexes by tapping his knee. The doctor
explained to Joaquin that the tapping sends a signal to his spinal cord. The
spinal cord then sends a signal to the muscle in Joaquin's thigh, and his leg
moves. Which of the following body systems is involved in this process?
A. Respiratory system
B. Nervous system
C. Skeletal system
D. Digestive system
Answer: Skeletal System
Explanation: Sense It's Sending up a signal up Joaquin's spinel cord It must be traveling threw his skeletal system
Answer:
its the nervous system because by tapping the knee, it will send a nerve down the neuron, through the mylein sheath and through the axon terminals to the receptors, which will recieve the nerve's signal and send it to the brain through the spinal cord in simple terms.
List 3 technologies that have made jobs easier.
Answer:
-security hardware
- artificial intelligence
wifi, internet, phones, voice assistants, drones.
How can flame color identify an unknown metal?
How can a spectrum positively identify an element?
How can astronomers tell which elements a star contains without a sample of it?
An amidation reaction is analogous to a(n) __________. View Available Hint(s) An amidation reaction is analogous to a(n) __________. esterification reaction in which an alcohol and a carboxylic acid react to form an ester acid hydrolysis reaction in which an amine is broken up into an amide and an alcohol base hydrolysis reaction in which an amine salt and an alcohol are formed esterification reaction in which an amine and an alcohol combine to make an amide
Answer:
esterification reaction in which an alcohol and a carboxylic acid react to form an ester
Explanation:
Esterification involves the reaction of an alcohol and a carboxylic acid to form an ester. This is an analogue of amidation which involves the reaction of a carboxylic acid with an amine to form an amide.
The relationship between the two reactions is that in both cases, the carbonyl (CO) group of the carboxylic acid is maintained and then bonded to a new moiety in the product. Water is formed in both reactions.
Hence, for esterification;
RCOOH + ROH ------> RCOOR + H2O
For amidation;
RCOOH + RNH2 -------> RCONHR + H2O
The_____
determines the quantity that can be produced by the reaction.
Answer:
C) limiting reagent
Explanation:
The limiting reagent is the reactant that you don't have a lot of, it will be completely used up in the reaction
17.4 mL of unknown H2SO4 solution was titrated by 0.20 M of NaOH. 41.51 mL of that NaOH solution was consumed to exactly completely neutralize the acid. What is the original molarity (in M) of the unknown H2SO4 solution?
Answer:
0.24 M
Explanation:
We'll begin by writing the balanced equation for the reaction. This is illustrated below:
H₂SO₄ + 2NaOH —> Na₂SO₄ + 2H₂O
From the balanced equation,
The mole ratio of the acid, H₂SO₄ (nₐ) = 1
The mole ratio of the base, NaOH (n₆) = 2
Finally, we shall determine the molarity of the acid. This can be obtained as follow:
Volume of acid, H₂SO₄ (Vₐ) = 17.4 mL
Molarity of base, NaOH (M₆) = 0.20 M
Volume of base, NaOH (V₆) = 41.51 mL
Molarity of acid, H₂SO₄ (Mₐ) =?
MₐVₐ / M₆V₆ = nₐ / n₆
Mₐ × 17.4 / 0.2 × 41.51 = 1 / 2
Mₐ × 17.4 / 8.302 = 1 / 2
Cross multiply
Mₐ × 17.4 × 2 = 8.302
Mₐ × 34.8 = 8.302
Divide both side by 34.8
Mₐ = 8.302 / 34.8
Mₐ = 0.24 M
Therefore, the molarity of the acid is 0.24 M
Which do you use to qualify matter?
A. Thermometer
B. Five senses
C. Balance
D. Tape measure
Answer:
c balance
Explanation:
if you weigh something, you prove it's there.
How is the molar mass of an element determined?
O A. The atomic mass unit times Avogadro's number is the molar
mass.
B. The number of moles in grams is the molar mass of the element.
C. The atomic mass in g/mol is the molar mass of the element.
D. The atomic number in g/mol is the molar mass of the element.
A rigid, insulated vessel is divided into two compartments connected by a valve. Initially, one compartment, occupying one-third of the total volume, contains air at 500oR, and the other is evacuated. The valve is opened and the air is allowed to fill the entire volume. Assuming the ideal gas model with variable specific heats. Determine: a. the final temperature of the air (in oR) b. the amount of specific entropy produced (in Btu/lbm oR)
Answer:
a) the final temperature of the air is 500° R
b) the amount of specific entropy produced is 0.0758 Btu/lb-°R
Explanation:
Given the data in the question;
Air at 500° R = [tex]T_i[/tex]
Using first law of thermodynamic;
δQ = dU + W
now, since the vessel is insulated, the transfer is zero, work done also is zero since there is also no external work done.
δQ = dU + W
0 = dU + 0
dU = 0
[tex]u_f[/tex] - [tex]u_i[/tex] = 0
[tex]u_f[/tex] = [tex]u_i[/tex]
hence, change in internal energy is 0
Now, since the ideal internal energy is a function of temperature, the temperature will also remain the same;
[tex]T_f = T_i[/tex]
F = 500° R
Therefore, the final temperature of the air is 500° R
b)
given that; initial volume is one-third of the total volume
V₁ = [tex]\frac{1}{3}[/tex]V₂
3V₁ = V₂
3 = V₂/V₁
Now, we take the value of gas constant R from air property table; gas constant R = 0.069 Btu/lb-R
so we calculate the entropy change;
Δs = [tex]c_v[/tex]In( [tex]\frac{T_2}{T_1}[/tex] ) + R.In( [tex]\frac{V_2}{V_1}[/tex] )
we substitute
Δs = [tex]c_v[/tex]In( [tex]\frac{500}{500}[/tex] ) + 0.069 × In( 3 )
Δs = 0 + [0.069 × In( 3 )]
Δs = 0 + [0.069 × 1.0986]
Δs = 0.0758 Btu/lb-°R
Therefore, the amount of specific entropy produced is 0.0758 Btu/lb-°R
Insulated vessels separate the environment of the outer and the inner system. The final temperature is 500 degrees R and 0.0758 Btu/lb- degree R is the entropy.
What is temperature?The temperature is the measure of the hot or the coldness of the system. The first law of the thermodynamics is used to measure the final temperature of the system:
[tex]\rm \Delta Q = \rm \Delta U + W[/tex]
The work done will be zero as the system is insulated and no external work is being done.
[tex]\begin{aligned} \rm 0 &= \rm \Delta U + 0\\\\\rm U_{f} - U_{i} &= 0\\\\\rm U_{f} &= \rm U_{i} \end{aligned}[/tex]
Hence, the change in the internal energy is zero. Thus, the final temperature will remain the same,
[tex]\rm T_{f} = \rm T_{i} = 500 ^{\circ} \rm R[/tex]
Now, as we know, the initial volume is one-third of the total volume then,
[tex]\begin{aligned} \rm V_{1} &= \rm \dfrac{1}{3} V_{2}\\\\\rm 3V_{1}&= \rm V_{2}\\\\3 &= \rm \dfrac{V_{1}}{V_{2}}\end{aligned}[/tex]
The change in entropy is calculated as:
[tex]\begin{aligned} \rm \Delta S &= \rm C_{v} ln ( \dfrac{T_{2}}{T_{1}}) + R \times ln ( \dfrac{V_{2}}{V_{1}}) \\\\&= 0 + [0.069 \times \rm ln( 3 )]\\\\& = 0.0758 \;\rm Btu/lb-^{\circ}R \end{aligned}[/tex]
Therefore, the entropy produced is 0.0758 Btu/lb- degree R.
Learn more about entropy here:
https://brainly.com/question/19538748
What is the elevation of Point B?
A. 800 ft
B. 900 ft
C. 850 ft
D. 1000 ft
How are cells organized?
A: Organs
B: Organelles
C: Tissues
Answer:
tissues,organs, organelles
It’s due in 3 minutes please help
Answer:
The Answer is gonna be Indroduction of non-native plant species
Which type of substances do you separate into ions when writing the complete ionic equation?
a. Aqueous
b. Liquid
c. Gas
d. Solid
Answer:
a. Aqueous
Explanation:
Took the test
Question 13 of 25
A scientist measures how quickly bamboo plants grow after receiving
different amounts of water. She gives each plant a different amount of water
and measures the plant's growth. What is the manipulated variable in this
experiment?
A. The total number of bamboo plants
B. The number of days of the experiment
C. The size of the bamboo plant
D. The amount of water given
What is the force being applied to an object with a mass of 12 KG and an acceleration of 4M/S
Answer:
48 newtons
Explanation:
4. The following occurs when heat energy is removed: Gas --A-> Liquid-B--> Solid.
What would be the phase change for A and B respectively?
A. Condensation, freezing
C. Condensation, melting
B. Melting, evaporation
D. Sublimation, deposition
Answer: The phase change for A and B respectively is condensation, freezing.
Explanation:
A process in which gaseous state of a substance converts into liquid state is called condensation.
For example, conversion of steam into water.
A process in which liquid state of a substance converts into solid state is called freezing.
For example, conversion of liquid water into ice.
Thus, we can conclude that the phase change for A and B respectively is condensation and freezing.
Condensation and freezing would be the phase change for A and B respectively.
What is Freezing?This is the process in which a liquid becomes solid and is mostly caused by exposure to cool temperatures.
Gaseous substances also have the ability to become liquids through the process known as Condensation. This therefore makes option A the most appropriate choice.
Read more about States of matter here https://brainly.com/question/9402776
8. The density of a gas at 350 C is 0,087 g/L. Compute the density at STP.
Answer:
0.20 g/L
Explanation:
Step 1: Calculate the molar mass of the gas (M)
At T = 350 °C = 623 K and P = 1 atm (we will assume this data), the density (ρ) of the gas is 0.087 g/L. We can calculate the molar mass of the gas using the following expression.
ρ = P × M/R × T
M = ρ × R × T/P
M = 0.087 g/L × (0.0821 atm.L/mol.K) × 623 K/1 atm = 4.5 g/mol
Step 2: Calculate the density of the gas at STP
At standard temperature (T = 273.15 K) and standard pressure (P = 1 atm), the density of the gas is:
ρ = P × M/R × T
ρ = 1 atm × 4.5 g/mol /(0.0821 atm.L/mol.K) × 273.15 K = 0.20 g/L
How are compositional layers distinguished?
Explanation:
The Earth has different compositional and mechanical layers. Compositional layers are determined by their components, while mechanical layers are determined by their physical properties.
The Earth has different compositional and mechanical layers. Compositional layers are determined by their components, while mechanical layers are determined by their physical properties.Information about the compositional layers
The Earth has different compositional and mechanical layers. Compositional layers are determined by their components, while mechanical layers are determined by their physical properties.Information about the compositional layersLayer Definition Depth
The Earth has different compositional and mechanical layers. Compositional layers are determined by their components, while mechanical layers are determined by their physical properties.Information about the compositional layersLayer Definition DepthCrust :The outermost solid layer of a rocky planet or natural satellite. Chemically distinct from the underlying mantle. 0-100km silicates
The Earth has different compositional and mechanical layers. Compositional layers are determined by their components, while mechanical layers are determined by their physical properties.Information about the compositional layersLayer Definition DepthCrust :The outermost solid layer of a rocky planet or natural satellite. Chemically distinct from the underlying mantle. 0-100km silicatesMantle :A layer of the Earth (or any planet large enough to support internal stratification) between the crust and the outer core. It is chemically distinct from the crust and the outer core. The mantle is not liquid. It is, however, ductile, or plastic, which means that on very long time scales and under pressure it can flow. The mantle is mainly composed of aluminum and silicates. 100-2900km iron and magnesium silicates
The Earth has different compositional and mechanical layers. Compositional layers are determined by their components, while mechanical layers are determined by their physical properties.Information about the compositional layersLayer Definition DepthCrust :The outermost solid layer of a rocky planet or natural satellite. Chemically distinct from the underlying mantle. 0-100km silicatesMantle :A layer of the Earth (or any planet large enough to support internal stratification) between the crust and the outer core. It is chemically distinct from the crust and the outer core. The mantle is not liquid. It is, however, ductile, or plastic, which means that on very long time scales and under pressure it can flow. The mantle is mainly composed of aluminum and silicates. 100-2900km iron and magnesium silicatesCore: The innermost layers of the Earth. The Earth has an outer core (liquid) and an inner core (solid). They are not chemically distinct from each other, but they are chemically distinct from the mantle. The core is mainly composed of nickel and iron. 2900-6370km meta
Given the following balanced chemical equation:
2C2H10 + 902 +4CO2 + 10H2O
How many moles of C2H10 are needed to completely react with 6.15
moles of oxygen?
O 1.37 mol
2 mol
0277 mol
Explanation:
[tex]6.15 \: mol \: oxygen \: \times \frac{2 \: mol \: c2h10}{9 \: mol \: oxygen} = 1.37 \: moles \: of \: c2h10 \: needed [/tex]
If it was helpfull, please select as brainliest answer. thanks;)
Both propanoic acid and propanone are soluble in water. Please draw a diagram and explain which compound is more soluble.
Answer:
Explanation:
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