Compared to a solution of pH 9, a solution of pH 7 is (d) 100 times more acidic.
The pH scale is a measure of the acidity or basicity of a solution. A solution with a pH of 7 is considered neutral, meaning it is neither acidic nor basic. A solution with a pH less than 7 is acidic, while a solution with a pH greater than 7 is basic.
In this case, we are comparing a solution with a pH of 7 to a solution with a pH of 9. The pH scale is logarithmic, meaning that a change of one unit on the scale represents a tenfold change in acidity or basicity. Therefore, a solution with a pH of 9 is 100 times more basic than a solution with a pH of 7 (10 to the power of 2).
To determine the answer, we need to remember that acidity and basicity are opposite properties. A solution with a higher acidity has a lower pH and a solution with a higher basicity has a higher pH.
Compared to a solution of pH 9, a solution of pH 7 is 100 times more acidic (10 to the power of -2). This means that the concentration of hydrogen ions (H⁺) in the pH 7 solution is 100 times higher than in the pH 9 solution.
Therefore, the correct answer is d. 100 times more acidic.
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An equimolar mixture of two optical isomers is called a ________. An equimolar mixture of two optical isomers is called a ________. enantiomer achiral diastereomer structural isomer racemic mixture
Two optical isomers can form:
An equimolar mixture of two optical isomers is called a racemic mixture.
What is a Racemic mixture?
An equimolar mixture of two enantiomers that is optically inactive is known as a racemic mixture (or racemate) (i.e. does not rotate plane-polarized light).
The racemic mixture can be created by:
Combining enantiomers in equal amounts, or (more frequently) Reactions that create one or more new chiral centers without the influence of chirality (i.e. chiral reagent, catalyst, etc.)The light that is plane-polarized does not spin in an optically inactive mixture.
Since each enantiomer rotates plane-polarized light to an equal and opposite extent, an equimolar mixture of two enantiomers will typically result in a racemic mixture. There won't be any net rotation if they are both present in equal proportions.
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Engine cooling fluid is a. distilled water. b. tap water from a faucet. c. a mixture of alcohol and water. d. a mixture of antifreeze and water.
Engine cooling fluid is a mixture of antifreeze and water.
Hence option (d) is correct.
A liquid mixture of water and antifreeze called engine coolant is kept in your car's radiator.
Any compound that lowers water's freezing point is considered antifreeze and protects a system against the negative effects of ice formation.
Radiators are protected from deterioration by antifreezes, which are frequently added to water in car cooling systems.
It keeps your engine from freezing in extremely cold weather or overheating in hot weather, both of which can cause serious problems for an engine.
Although it's standard practice to combine water and antifreeze 50/50 in a car's cooling system, this guideline is not inflexible.
Mixtures can be changed to either raise the boiling point or lower the freezing point limit due to the wide range of weather conditions that cars can operate in.
Hence, Engine cooling fluid is a mixture of antifreeze and water.
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What is occurring when reactants are mixed and heated and liquid collects in the sidearm of the apparatus
When reactants are mixed and heated and liquid collects in the sidearm of the apparatus, a chemical reaction is occurring.
What is a chemical reaction?A chemical reaction is said to occur when reactants are combined to form products. We must note that the formation of products is evidenced by;
Appearance of a liquidAppearance of a gas Appearance of a solidHence, when reactants are mixed and heated and liquid collects in the sidearm of the apparatus, a chemical reaction is occurring.
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The solubility of lead(II) chloride is 0.45 g/100 mL of solution. What is the Ksp of PbCl2?a. 8.5 ? 10^-6b. 4.2 ? 10^-6c. 1.7 ? 10^-5d. 4.9 ? 10^-2e. < 1.0 ? 10^-6
The solubility of lead(II) chloride is 0.45 g/100 mL of solution. The value of [tex]K_{sp}[/tex] of [tex]PbCl_{2}[/tex] is 1.7×[tex]10^{-5}[/tex] .
So, option C is correct one.
Calculation,
Number of moles of [tex]PbCl_{2}[/tex] = mass/molar mass = 0.45/278.1 = 1.618×[tex]10^{-3}[/tex] moles
Concentration of [tex]Pb^{+2}[/tex] and [tex]Cl^{-}[/tex] ion
Molarity of [tex]Pb^{+2}[/tex] = Number of moles of solute /volume in lit
Molarity of [tex]Pb^{+2}[/tex] = 1.618×[tex]10^{-3}[/tex] moles /0.1 lit = 0.0162 M
[tex]PbCl_{2}[/tex] → [tex]Pb^{+2}[/tex] + 2[tex]Cl^{-}[/tex]
For certain amount of [tex]Pb^{+2}[/tex] , twice this amount of [tex]Cl^{-}[/tex] ion formed.
The concentration of [tex]Cl^{-}[/tex] ion formed = 2× 0.0162 M = 0.0324 M
Now,
The solubility of lead(II) chloride of solution = 0.45 g/100 mL
[tex]K_{sp}[/tex] of [tex]PbCl_{2}[/tex] = [ [tex]Pb^{+2}[/tex] ][tex][Cl^{-}]^{2}[/tex] = 0.0162 ×[tex][0.0324 ]^{2}[/tex] = 1.7×[tex]10^{-5}[/tex] .
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Once ____________ bonds form between every fourth amino acid in a polypeptide chain, the chain begins to twist into the ____________ structure known as a(n) ____________ .
Once hydrogen bonds form between every fourth amino acid in a polypeptide chain, the chain begins to twist into the secondary structure known as a(n) alpha helix.
What is Amino Acid ?
Amino acids are organic compound. Amino acids contains amine and carboxyl functional group. Amino acids is the building block of life these are the molecules that combine to form proteins.
What is Polypeptide Chain ?A unique sequence of amino acids joined by peptide bonds is called polypeptide.
Thus from the above conclusion we can say that Once hydrogen bonds form between every fourth amino acid in a polypeptide chain, the chain begins to twist into the secondary structure known as a(n) alpha helix.
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Identify the products of the reaction between 2KOH and H₂SO4.
O KSO and H2₂O
OK2SO4 and H₂O
O H₂O and K₂SO4
O KH2 and SO4
Answer:
C.) H₂O and K₂SO₄
Explanation:
This appears to be a double-displacement reaction. In these reactions, the cation of one substance is swapped with the cation of another.
So, K⁺ from KOH is swapped with the H⁺ from H₂SO₄. The new compounds should have an overall charge of 0. Therefore, it may be necessary to modify the amount of each ion (not just be 1:1).
K₂SO₄
-----> K⁺ and SO₄²⁻
-----> + 1 + 1 + (-2) = 0
H₂O
-----> H⁺ and OH⁻
-----> + 1 + (-1) = 0
As a reaction proceeds toward equilibrium from reactants to products (i.e., from left to right as written), the value of Q is
As a reaction proceeds toward equilibrium from reactants to products, the value of Q is Increasing
Equilibrium can exist in chemical processes (the products and reactants are produced at the same rate). In a reversible chemical reaction, chemical equilibrium is the state in which there is no net change in the quantity of reactants or products. When a chemical reaction is reversible, the products react with the original reactants as soon as they are created.
There is no net change in the quantity of the chemicals involved when the two opposing reactions are in equilibrium because they are occurring at identical rates, or velocities. At this point, the reaction may be deemed to be finished, meaning that the maximum amount of reactants to products has been converted under the given reaction conditions.
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In an ionic lattice:
A. atoms are packed together in a regular cubic arrangement
B. atoms are bonded with 2 single bonds and one double bond.
C. atoms are structured in a vast network of atoms.
D. atoms are bonded to four others in a tetrahedral shape.
In an ionic lattice, atoms are packed together in a regular cubic arrangement; option A.
What is an ionic compound?
An ionic compound is a compound which is composed of oppositely-charged ions which are held together by strong electrostatic forces of attraction.
The properties of ionic compound include:
They occur in regular crystal latticesThey have high melting and boiling pointsThey are electrolytes.Ionic lattices have regular structural patterns consisting of atoms arranged in a regular repeating pattern, usually a cube. There are several cubic structures in ionic lattices.
In conclusion, ionic lattices are regular repeating arrangement of atoms. Ionic lattices are usually arranged in the form of cubic crystal.
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15. What is the mass of mercury in a 250 g fish if the ppm was measured to be 0.23?
Answer: The mass of mercury will be 57.5 micrograms.
The given question deals with Analytical Chemistry where Concentration is asked here.
Concentration: Generally concentration is defined as amount of the substance per unit volume. Concentration is also expressed in parts per million(ppm) when it is a small quantity as in case of mercury content in fish.
Explanation: Given mass of the fish = 250 g,
ppm = 0.23
Now mass of mercury = 0.23 ppm × 250 g
= 0.23/1,000,000 × 250g
=0.23×250/1,000,000 g
= 0.0000575 g
=57.5 micrograms
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A sample of hydrogen gas collected at a pressure of 0.923 atm and a
temperature of 17.0 °C is found to occupy a volume of 29.6 liters. How many
moles of H₂ gas are in the sample?
mol
Answer:
1.15 moles H₂
Explanation:
To find the moles of H₂ gas, you need to use the Ideal Gas Law equation. The equation looks like this:
PV = nRT
In this equation,
-----> P = pressure (atm)
-----> V = volume (L)
-----> n = moles
-----> R = Ideal Gas Constant (0.08206 L*atm/mol*K)
-----> T = temperature (K)
Before you can plug the given values into the equation and simplify, you need to convert Celsius to Kelvin.
P = 0.923 atm R = 0.08206 L*atm/mol*K
V = 29.6 L T = 17.0 °C + 273.15 = 290.15 K
n = ? moles
PV = nRT
(0.923 atm)(29.6 L) = n(0.08206 L*atm/mol*K)(290.15 K)
27.3208 = n(23.809709)
1.15 = n
The table shows the concentration of a reactant in the reaction mixture over a period of time.
Reactant Concentration
Time Concentration
Os 1.8 M
210 s 1.2 M
450 S 0.8 M
580 S 0.6 M
720 s 0.4 M
What is the average rate of the reaction over the first 450 seconds? (3 points)
Ob
Oc
Od
1.7 x 10-3
1.9 x 10-3
2.0 x 10-3
2.2 x 10-3
The average rate of the reaction over the first 450 seconds -2.2×10⁻³ M/s
What is speed?Speed is defined as the rate of change of the distance moved with time. Mathematically, it can be expressed as:
Speed = distance / time
With the above idea, we can obtain the rate of the reaction as illustrated below:
How to determine the rate of the reaction over the first 45osChange in concentration = 0.8 - 1.8 = -1 MTime = 450 sSpeed = ?Rate = Change in concentration / time
Rate = -1 / 450
Rate = -2.2×10⁻³ M/s
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D is correct for number 2. i just finished
explanation; i got it right
Explain why the production of a gas in this experiment is or is not different from the formation of water vapor in the heating curve experiment.
The production of a gas is different because unlike the heating curve, there was no heat applied to this experiment, and the experiment was a chemical reaction.
What is a Heating curve?This shows the relationship between the temperature of the heating system and the air temperature in the outer environment.
The chemical reaction emitted heat as against the other which involved heat application which is why water formation in this curve was different.
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In the reaction catalyzed by the pyruvate dehydrogenase complex, the two carbons constituting the acetyl group are.
In the reaction catalyzed by the pyruvate dehydrogenase complex, the two carbons constituting the acetyl group are oxidized by NAD+ while attached to the lipoamide.
Pyruvate dehydrogenase influencing the reaction:A multienzyme complex called pyruvate dehydrogenase (PDH) catalyzes the oxidative conversion of pyruvate into acetyl coenzyme A (CoA), carbon dioxide (CO2), and reducing equivalents in the form of NADH.
Reaction:The pyruvate dehydrogenase complex catalyzes the oxidative decarboxylation of pyruvate to the acetyl group of acetyl-CoA.This complex requires the sequential action of three different enzymes and five different enzymes and five different coenzymes or prosthetic groups - Thiamine pyrophosphate(TPP), flavin adenine dinucleotide(FAD), coenzyme A(CoA-SH), Nicotinamide adenine dinucleotide(NAD).To learn more about catalysis visit:
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Complete the charge balance equation for an aqueous solution of h2co3 that ionizes to hco−3 and co2−3.
The relevant coefficients for each species on the right side of the equation in order to balance the charges.
We can add a coefficient of 2 to HCO³⁻ and a coefficient of 1 to CO3- because the charges must cancel out: H₂CO₃ ⇌ 2HCO³⁻ + CO₃²⁻-
The charges balance is now: No initial charge
Charge total: 2(-1) + (-2) = -4
Due to the balance of the charges, the charge balance equation is as follows: H₂CO₃ ⇌ 2HCO³⁻- + CO₃²⁻.
,Thus, The charge balance equation is as follows: H₂CO₃ ⇌ 2HCO³⁻- + CO₃²⁻.
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An iron bar at 200°c is placed in thermal contact with an identical iron bar at 120°c in an isolated system. after 30 minutes, both iron bars are at 160°c. if the iron bars were placed in thermal contact in an open system instead of an isolated system, how would the results be different? assume that the room temperature is 25°c.
Place the items in order from lowest to highest degree of internal organization
The order of internal organization from lowest to highest degree is; cell < tissue < organ < organ system
What is the order of organization?The complexity of the parts that compose an organism lays the bedrock for the classification of life. Some organisms are composed only of one cell while others are composed of many complex systems.
The order of internal organization from lowest to highest degree is; cell < tissue < organ < organ system
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Missing parts:
Place the items in order from lowest to highest degree of internal organization.
1.organ system
2.tissue
3.cell
4.organ
Nylon, a polyamide, is produced from hexanediamine and a substance, x. This substance, x, is most probably:____.
a. an amine.
b. a carboxylic acid.
c. a nitrile.
d. an alcohol.
Nylon, a polyamide, is produced from hexanedi-amine and a substance, x. This substance, x, is most probably a carboxylic acid.
A polymer containing repeating units connected by amide bonds being called a polyamide. Both naturally occurring and synthetic polyamides are found. Proteins found in materials like wool and silk were examples of naturally produced polyamides.
The term "nylon" refers to a family of polymeric materials made up of polyamides. Nylon would be a silk-like thermoplastic that may be formed into threads, films, or other shapes. It is often manufactured from petroleum.
Therefore, Nylon, a polyamide, is produced from hexanedi-amine and a substance, x. This substance, x, is most probably a carboxylic acid.
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Potassium carbonate dissolves as follows:
K2CO3(s) → 2k (aq) CO3^2-(aq).
What volume in liters of 1.0 m k2co3 solution is required to provide 0.50 moles of k (aq)?
The 0.25 volume in liters of 1.0 M [tex]K_{2}CO_{3}[/tex] solution is required to provide 0.5 moles of [tex]K[/tex](aq).
Calculation,
The Potassium carbonate dissolves as follows:
[tex]K_{2}CO_{3}(s)[/tex] → [tex]2K(aq) +[/tex][tex]CO_{3}^{-2} (aq)[/tex]
The mole ratio is 1: 2
It means, the 1 mole [tex]K_{2}CO_{3}[/tex] required to form 2 mole of [tex]K[/tex](aq).
To provide 0.5 mole of [tex]K[/tex](aq) = 1 mole ×0.5 mole /2 mole required by [tex]K_{2}CO_{3}[/tex].
To provide 0.5 mole of [tex]K[/tex](aq) ,0.25 mole required by [tex]K_{2}CO_{3}[/tex].
The morality of [tex]K_{2}CO_{3}[/tex] = 1 M = number of moles / volume in lit
The morality of [tex]K_{2}CO_{3}[/tex] = 1 M = 0.25 mole/ volume in lit
Volume in lit = 0.25 mole / 1 M = 0.25 mole/mole/lit = 0.25 lit
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is generally regarded as one of the most accomplished and influential
scientists in history.
answer - Albert Einstein
explanation -
Albert Einstein is arguably the most influential scientist of the 20th century. His … general theory of relativity changed our understanding of space and time, becoming one of the two pillars of modern physics – the other being quantum mechanics.
Which is not considered part of the solar system?
Jovian planets
galaxies
terrestrial planets
sun
Galaxies is not the part of the Solar system.
Hence, Option B is correct answer.
What is Solar System ?Solar System is made up of all the planets that revolve around our Sun. Solar System contains eight planets. These planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.
Now lets check all options one by one
Option (A): Jovian Planets
Outer planets are called Jovian planets. These planets are Jupiter, Saturn, Uranus and Neptune. So Jovian Planets are part of the Solar System.
Hence, Option A is incorrect.
Option (B): Galaxies
Galaxy has a black hole at its center. It is a huge collection of dust, billions of star and gas. So galaxies are not a part of the Solar system.
Hence, Option B is incorrect.
Option (C): Terrestrial Planets
Innermost planets in solar system are Terrestrial planets. These planets are Mercury, Venus, Earth and Mars. So Terrestrial planets are part of the Solar system.
Hence, Option C is incorrect.
Option (D): Sun
The Sun is the part of the Solar system as it is the only star in our Solar system. Sun is the center of our Solar system.
Hence, Option D is incorrect.
Thus from the above conclusion we can say that Galaxies is not the part of the Solar system.
Hence, Option B is correct answer.
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Which fundamental mechanisms appear in the reaction between pyridinium chlorochromate and a secondary alcohol
The idea is to foretell the formation of a carbonyl compound by the reaction between alcohol and too much pyridinium chlorochromate. An oxidizing agent called pyridinium chlorochromate converts the alcohol group into the 1carbonyl group.
The carbonyl molecule that results from the reaction will depend on the reactant's OH group. Pyridinium chlorochromate [PCC] converts primary OH to aldehydes, whereas it converts secondary OH to ketones, and oxidation of tertiary OH has little effect. Alcohols and pyridinium chlorochromate [PCC] react to create a carbonyl molecule.
From primary alcohols to aldehydes and from secondary alcohols to ketones, pyridinium chlorochromate oxidizes alcohols one step up the oxidation ladder. pyridinium chlorochromate will not oxidize aldehydes to carboxylic acids, in contrast to chromic acid. Comparable to Pyridine (the Collins reagent) and CrO3 will both oxidize primary alcohols to aldehydes. Here are two instances of pyridinium chlorochromate being used.
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A radioisotope decays, producing an alpha particle and th-234. the original radioisotope must have been an atom of?
If the product of the process is Th-234, the we now know that the original atom must be U-238.
What is an alpha decay?An alpha decay is said to occur when there is the loss of an alpha particle from an atom. Now we know that when there is a loss of an alpha particle, the mass number is decreased by 4 four units while the atomic number is decreased by two units.
If the product of the process is Th-234, the we now know that the original atom must be U-238. It is found two places after the thorium atom in the periodic table.
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a major textile dye manufacutrer developed a new yellow dye. the dye has a percent composition of 75.95%C, 17.72%n and 6.33%H by mass with a molar mass of about 240g/mol. determine the molecular formula of the dye
The molecular formula of dye:
A major textile dye manufacturer developed a new yellow dye with a molecular formula [tex]C_{15}N_{3}H_{15}[/tex].
Given:
Percentage composition:
C = 75.95%
N = 17.72%
H = 6.33%
Molar mass = 240 g
To find: molecular formula of dye
Calculation:
Let's assume the mass of the compound is 100 gm.
So, Mass of C = 75.95 gm
Mass of N = 17.72 gm
Mass of H = 6.33 gm
The number of moles = given mass/mass
Therefore, the number of moles of C = 75.95/12 = 6.33
The number of moles of N = 17.72/14 = 1.27
Number of moles of H =6.33/1 = 6.33
Simplest ratio:
C = 6.33/1.27 = 4.98 =5
N = 1.27/1.27 = 1
H = 6.33/1.27 = 4.98 =5
Therefore, the empirical formula is [tex]C_{5}NH_{5}[/tex]
The mass of empirical formula = 12 x 5 + 14 + 1 x 5 = 79 gm
Number of moles= molar mass/ empirical formula
n = 240/79 = 3.04 =3
Therefore, molecular formula = empirical formula x n
Hence, molecular formula = [tex]C_{15}N_{3}H_{15}[/tex]
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The oxidation number is often referred to as the _____. redox factor oxidation state spectator ion reducing factor
The oxidation number is often referred to as the oxidation state.
The number of electron/electrons which completely transferred and induced charged on an atom is called oxidation state of an atom. It is also describe as the number that is allocated to elements in a chemical combination. The number of electron that atoms in a molecule can share while forming chemical bonds with other atoms of a different elements. The oxidation number of the monoatomic (composed by atom) ion is the same as the charge of the ion.
The primary distinction between oxidation number versus oxidation state would be that the former refers to the charge that would be placed on the central atom of a coordination complex if every one of the connections around it were ionic bonds, while the latter relates to the number of electrons that an atom could either receive, lose, or share with some other atom.
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Elements on the periodic table are arranged in order by their
Answer:
in order of increasing atomic number, or the number of protons in an atom's nucleus, which generally coincides with increasing atomic mass
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The function of the heat exchanger in a nuclear reactor is to...
Select one:
a. prevent the leakage of radiation into the environment.
b. convert water into steam, which turns a turbine.
c. cool the reactor water.
d. absorb neutrons to slow down the chain reaction.
Answer:
cool the tractor water system
What do you think the elements that are in the same group or period on the periodic table have in common?
chemical properties and same number of shell
Explanation:
elements in the same group have the same number of eletrons in their outermost shell and hence have the same chemical properties
Calculate the number of atoms in 3 mol helium
Answer:
1.81 x 10²⁴ atoms He
Explanation:
You can find the amount of atoms by multiplying the given moles by Avogadro's Number. This number represents the amount of atoms per 1 mole. It is important to arrange the ratio in a way that allows for the cancellation of units.
Avogadro's Number:
6.022 x 10²³ atoms = 1 mole
3 moles He 6.022 x 10²³ atoms
-------------------- x -------------------------------- = 1.81 x 10²⁴ atoms He
1 mole
What is the coefficient for oh−(aq) when s2−(aq) no3−(aq) → s(s) no(g) is balanced in basic aqueous solution?
From the balanced redox equation of the reaction, the coefficient of OH⁻ is 8.
What is the balanced redox equation of the reaction?A redox equation is the equation of a redox reaction in which oxidation and reduction occurs simultaneously.
The given redox reaction takes place in a basic solution
The balanced redox equation of the reaction is given below:
4 H₂O(l) + 3 S²⁻(aq) + 2 NO₃⁻(aq) ---> 3 S(s) + 2 NO + 8 OH⁻(aq)
In conclusion, a redox equation is balanced when oxidation and reduction occur to the same extent.
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What kind of defect or dislocation does a carbon in a ti metal lattice represent?
electrical conductivity is the kind of defect or dislocation a carbon in a ti metal lattice represents.
The electrical conductivity of a metal is the result of the movement of charged particles. Atoms of metal elements are electrons in the outer shell of the atom and are characterized by the presence of valence electrons that can move freely around
Staircase dislocations and Lomer-Cottrell dislocations are examples of fixed dislocations. The two main types of movable dislocations are blade dislocations and spiral dislocations. The blade dislocations can be visualized as being caused by the termination of the atomic plane at the center of the crystal.
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