Answer:
Explanation: The best-supported theory of our universe's origin centers on an event known as the big bang. This theory was born of the observation that other galaxies are moving away from our own at great speed in all directions as if they had all been propelled by an ancient explosive force.
You are using a microscope with a 10x eyepiece. What is the approximate focal length of an objective lens which will give a total magnification of 200x? assume a tube length of 160 mm.
The approximate focal length of an objective lens is 8.42 mm.
The magnification of eye piece (m1)=10
Total magnification (m)=200
using,
m=m1*m2
200=10*m2
m2=20
Thus, magnification of objective lens=20
Using the formula for magnification of objective lens,
m2=1+L/f
20=1+0.16/f
f=0.16/19
=0.00842 m
8.42 mm
Therefore, the focal length is 8.42 mm.
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Every second, the Sun converts about 600 million tons of hydrogen into 596 million tons of helium. The remaining 4 million tons of mass is _________.
converted to an amount of energy equal to 4 million tons times the speed of light squared
ejected into space in a solar wind
reabsorbed as molecular hydrogen
ejected into space by solar flares
translated into 4 million tons of energy multiplied by the square of the speed of light.
What percentage of the Sun's mass is converted to energy per second?The Sun undergoes this reaction throughout, and as a result, 600 million tons if hydrogen are converted in 596 million tons or helium each second.E=mc² states that the 4 million tons that missing matter are transformed into energy.
How much of the Sun's hydrogen gets changed into helium every day?The sun makes 598 tons of helium and burns 600 million tons of hydrogen each second.The remaining 4 million tons per day are turned into electricity.
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What are the different types of chemical bonds list the 3 types of bonds from strongest to weakest and describe each type of bond?
A chemical bond can be formed by exchange of electrons, sharing of electrons.
There are so many types of chemical bonds but majorly three types of chemical bonds are:
Ionic Bond,
Covalent Bond,
and Metallic Bonds.
And out of these three types of bonds, Ionic Bonds are the strongest bonds.
The order from strongest to weakest bond is given as :
Ionic Bond > Covalent Bond > Metallic Bond
Ionic Bond: When an atom lose or gain the electron to attain the stability it forms ions and the attractive forces between two oppositely charged ions is known as ionic attractions or electrostatic attractive forces.
and such formed bonds are known as ionic bonds.
An ionic bond is formed when the difference between the electronegativities of two atoms is high as an electron transfer to occur to form the ions.
Covalent Bond: A covalent bond consists of the mutual sharing of one or more pairs of electrons between two atoms.
A covalent bond is formed when the electronegativity difference of two atoms is too small for an electron transfer to occur to form ions.
Metallic Bonds: Metallic bonds are made up of electrostatic attraction between metal cations and the delocalized electrons. Metallic bond is collective sharing of valence electrons between several positively charged metal ions.
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Given that S is the central atom in OSF4, draw the LewisStructure in which the formal charges of all atoms are zero.Include any lone pair electrons.
In a schematic illustration of a compound called a Lewis structure, the atoms and their associated electrons are shown.
Which Lewis structure for SOF4 has the most lone pairs overall?As a result, each fluorine and oxygen atom contains three lone electron pairs and six non-bonding electrons.
What part of OSF4's structure does the oxygen atom most likely occupy?The equatorial plane The two F atoms would occupy the axial places in accordance with Bent's Rule, and the other two F atoms, along with the oxygen atom, would occupy the equatorial positions. This would result in a triangular bipyramidal structure.
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The united states mint uses electrolysis to copper plate zinc pennies by placing them in a cu2+ solution and connecting the pennies and a copper electrode to a battery. Enter the half-reaction that takes place when the pennies are plated with solid copper. Include phases.
Cathode reaction: [tex]Cu^{2+} + (aq) + 2e-- > Cu (s).\\[/tex]
Anode reaction: [tex]Cu(s) -- > Cu^{2}+ (aq) + 2e[/tex] is
What is half-reaction?
A redox reaction's oxidation or reduction reaction component is known as a half reaction (or half-cell reaction). By taking into account the change in oxidation states of specific chemicals participating in the redox reaction, a half reaction is produced.
Here Zn pennies act as cathode , reduction of [tex]Cu^{2+}[/tex] to Cu take place here.
Cu rod acts as anode,here dissolution of Cu (s) to [tex]Cu^{2+}[/tex] take place .
Half cell reactions
Cathode reaction: [tex]Cu^{2+} + (aq) + 2e-- > Cu (s).\\[/tex]
Anode reaction: [tex]Cu(s) -- > Cu^{2}+ (aq) + 2e[/tex]
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what is the product of the reaction of bromoethane with each of the following nucleophiles?
1-butyne is the product that is formed by the reaction of bromoethane and the following nucleophile sodium acetylide.
Definition of nucleophilic substitution reaction
Nucleophilic substitution reactions are a class of reactions in which an electron rich nucleophile attacks a positively charged electrophile and replaces a leaving group. For alginate reactions, the most reactive nucleophile is considered as the C6 carboxylate group.
1-butyne is the product formed from the reaction between bromoethane and sodium acetylide. This reaction is a nucleophilic substitution type reaction where acetylide ion act as nucleophile. General reaction is given below:
C₂HNa + C₂H₅Br → CH₃CCHCH₂ + NaBr
1-butyne is the product formed in this reaction.
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What is a homogeneous mixture in which a substance is dissolved in a liquid?
A homogeneous mixture in which a substance is dissolved in a liquid is a solution.
A homogeneous mixture is the that has the same proportion of the components through out the mixture. a homogeneous mixture has the uniform composition through out the mixture. The liquid is called as the solvent which dissolves the other substances is called as the solute. there are some examples of homogeneous mixtures are :
Air sugar waterrain watersalt watervinegarin the homogeneous mixture we can not distinguish the the components of the mixture. so, a solution is a homogeneous mixture in which a substance is dissolved in a liquid.
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Select all the statements that correctly describe the arrangement of individual particles in the three physical states of matter. Relate these particulate views to the observable properties of matter.
Gases occupy the entire volume of the container.
The particles in a solid move quite freely.
The particles in a solid occupy fixed positions.
Liquids take the shape of the container.
Liquids have the same fixed arrangement of particles as observed in solids.
The particles in a gas move quite freely.
The correct statements are statement 1 (Gases occupy the entire volume of the container), statement 3 (The particles in a solid occupy fixed positions), statement 4 (Liquids take the shape of a container), and statement 6 (The particles in a gas move quite freely).
The term "matter" refers to anything that occupies space and has mass. There are three different states of matter: solid, liquid, and gas.
Solids have distinct volumes and shapes. They are not compressible and are densely populated. The particles of a solid are attracted to one another with a powerful force. The distance between solids' particles is minuscule. The particles in a solid are in a fixed location.
A liquid cannot be compressed because it has a fixed volume. They don't have a fixed shape; instead, they take on the shape of the vessel they are placed in.
Gases are compressible. To fill their vessels, gases enlarge. They take up a lot more space than the liquids or solids they originate from.
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arrange the organic compounds from most soluble in water to least soluble in water.a. CH3CH3b. CH3OCH3c. CH3CH2OH1. most soluble in water2. least soluble in water
The organic compounds from most soluble in water to least soluble in water is CH3CH2OH, CH3CH3 and CH3OCH3.
The degree to which a substance dissolves in a solvent to form a solution is known as solubility ( expressed as grams of solute per liter of solvent). One fluid's ability to completely dissolve another fluid (liquid or gas; for example, methanol and water) or only partially do so (oil and water dissolve only slightly). "Like dissolves like," in general ( aromatic hydrocarbons dissolve in each other but not in water). According to the distribution coefficient (the ratio of a material's solubilities in two solvents), some separation techniques (such as absorption and extraction) rely on differences in solubility. In general, as temperature rises, so do the solubilities of solids in liquids, while they fall as temperature rises and rise with pressure for gases. A solution is said to be saturated when no more solute can dissolve in it at a specific temperature and pressure.
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calculate the mass of calcium chloride (cacl2) that is needed to form a 100.0 ml solution of 0.150 m cacl2.
Mass of CaCl2 is 11g .
What is Molar Mass?
We all wish to know how many molecules are there in a given material. Atoms and molecules are very small in both size and mass. One sample mole's weight is the molar mass. To get the molar mass, connect the atomic masses (atomic weights) of each atom in the molecule. Using the mass listed in the Periodic Table or Atomic Weight Table, determine the atomic mass for each element.
Typically, molar mass is stated in either grammes (g) or kilogrammes (kg) (kg).
(100mL) (1L)/1000mL = 0.1 L is the volume of solution in litters.
CaCl2 has a molarity of 1 mole/L and a molar mass of 110 g/mole.
CaCl2 solute mass equals
M = mol of solute per litre of solution; mol of solute equals mol mass of solute divided by molar mass
Mass of the solute is equal to M x L of solution x its molar mass.
CaCl2 mass equals 1 mole/L, 0.1 L, and 110 g/mole, or 11 g CaCl2.
The mass of CaCl2 is equal to 11g CaCl2.
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Does P and Cl form an ionic bond?
on a hot summer day, you make a glass of refreshing sweet iced tea by combining boiling water, tea, sugar, and ice. what type of change occurs and how do you know?
A physical change will occur when boiling water, tea, sugar, and ice are combined to form sweet iced tea.
What is a physical change?A physical change is a change affecting the form of a chemical substance, but not its chemical composition.
The characteristics of some physical changes are as follows:
textureshapetemperaturechange in the state of matterAccording to this question, one makes a glass of refreshing sweet iced tea by combining boiling water, tea, sugar, and ice on a hot summer day. The resulting solution is an example of a mixture, which contains constituents that retain their individual identity.
This suggests that the change is a physical change because there is no formation of a new substance.
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indicate the hybridization of the specified atoms. be sure to consider any lone pairs you added to the structure. the structure of cyanazine has 5 atoms highlighted. atom 1 is an n atom bonded to 2 c atoms and 1 h atom through single bonds. atom 2 is an n atom bonded to one c atom through a single bond and one c atom through a double bond. atom 3 is a c atom bonded to one c l atom and one n atom through a single bond and one n atom through a double bond. atom 4 is a c atom that is bonded to three c atoms and one n atom through single bonds. atom 5 is a c atom that is bonded to one c atom through a single bond and one n atom through a triple bond. what is the hybridization of atom 1?
The atom bearing the number 1 has an sp3 hybridization. The hybridization is sp3 because there are four groups surrounding this atom, along with two lone pairs of electrons and two bonds.
How can we quickly tell whether atoms have hybridized?Only the quantity of lone pairs and sigma bonds around an atom are taken into account for determining its hybridization.
The term "hybridization" means what?
When two atomic orbitals join to form a hybrid orbital in a molecule, the energy of the separate atomic orbitals is redistributed to give orbitals of equivalent energy.
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What is bond answer in one sentence?
A chemical bond can be interaction between atoms or ions that enables the formation of molecules and crystals.
A chemical bond can be formed by exchange of electrons, sharing of electrons.
When an atom lose or gain the electron to attain the stability it forms ions and the attractive forces between two oppositely charged ions is known as ionic attractions or electrometric attractive forces.
and such formed bonds are known as ionic bonds.
An ionic bond is formed when the difference between the electronegativities of two atoms is high as an electron transfer to occur to form the ions.
A covalent bond consists of the mutual sharing of one or more pairs of electrons between two atoms.
A covalent bond is formed when the electronegativity difference of two atoms is too small for an electron transfer to occur to form ions.
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What is the frequency of an x-ray wave with an energy of 2×10 to the power of -17 jewels in hertz
The frequency of an x-ray wave with an energy of 2×10^(-17) J in hertz is 3.01 × 10^(16) hz.
We can find the value of frequency of an x ray wave by using the relation between energy and frequency.
As we know that,
Energy is directly proportional to the frequency of the wave.
Mathematically,
E = h. f
Where,
E is the energy in joule
f is the frequency of the wave in hertz
h is the planck's constant
Given,
E = 2 × 10^(-17)J
h = 6.63 × 10^(-34) kg.m2/s
By substituting all the values, we get
2 × 10^(-17)J = 6.63 × 10^(-34) kg.m2/s × f
f = 2 × 10^(-17)J / 6.63 × 10^(-34) kg.m2/s
f = 3.01 × 10^(16) hz.
Thus, we concluded that the frequency of an x-ray wave with an energy of 2×10^(-17) J in hertz is 3.01 × 10^(16) hz.
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why did the big bang not produce a significant proportion of elements heavier than helium?
Only so long as it didn't get too cold for heavier elements to form could helium survive.
What prevented the Big Bang from producing more heavy elements?Big Bang nucleosynthesis produced incredibly few stable nuclei of elements heavier than lithium because of a bottleneck brought on by the absence of a stable nucleus with 8 or 5 nucleons. Additionally, this lack of larger atoms limited the quantity of lithium-7 that could be produced during BBN.
Why didn't more massive atoms than helium form in the first few seconds of creation?The early cosmos was too hot before a few minutes into the expansion for atoms to form. Only a few minutes remained before it became too cold to continue nucleosynthesis and prevent the formation of new elements.
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3. A force is a push or a pull. What happens to an object that the magnets attract?
Answer:
it pulls
Explanation:
it pulls because of the magnetic force
Answer: It is pulled
Explanation:
Deeming that the force of motion is attraction, the only way it could be moving would be in pull of the magnet.
(a) is it possible to grind up and reuse phenol-formaldehyde? why or why not? (b) is it possible to grind up and reuse polypropylene? why or why not?
Phenol-formaldehyde is a thermoset polymer. Thermoset polymers can not be heated up and reused. Therefore it is not possible.
What is Polymer?
The Greek word for "polymer" is "many pieces." Everywhere we look, we encounter polymers. From the strand of human DNA, a biopolymer that naturally occurs, to polypropylene, a material that is used all over the world.
Natural polymers are those found in plants and animals; synthetic polymers are those manufactured by humans (synthetic polymers). Due to their many distinctive physical and chemical characteristics, several polymers are used in daily life.
All polymers are produced by the process of polymerization, in which their component parts, known as monomers, combine with one another to form polymer chains, or 3-dimensional networks that form the links in polymers.
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explian why potassium chloride, KCI will not dissolve in carbon tetrachloride,CCI4?
Arrange the colors of the visible spectrum in order from highest to lowest energy !
The colors of the visible spectrum are in order from the highest to lowest energy which is : Violet Indigo Blue Green Yellow Orange and Red.
Red light has the lowest energy since it has the longest visible light wavelength. The highest energy visible light is violet since it has the shortest wavelength. The visible light spectrum has energies ranging from red to violet, and the human brain perceives these energy as different hues. Violet has the highest energy whereas red has the lowest. Red light, which has the lowest visible light frequency, has the least energy. The order spectrum reveals frequency content, just like the power spectrum does.
However, the order spectrum offers extra information about harmonically connected rotating machinery systems. Orders are frequency multiples of the reference velocity that are specific.
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Which element has the same number of energy levels as krypton (kr) and the same number of valence electrons as nitrogen (n)?.
The element that has the same number of energy levels as Krypton (Kr) and the same number of valence electrons as Nitrogen (n) is Arsenic (As).
What are valence electrons?Electrons аre sub-аtomic pаrticles thаt аre present in the аtom аnd cаrry а negаtive chаrge. The electrons were discovered by J.J. Thompson. The electrons revolve аround the nucleus in vаrious shells аnd аid in the formаtion of bonds.
Vаlence electrons аre the totаl number of electrons thаt аn аtom cаn shаre to form bonds. Nitrogen is the element thаt hаs the sаme number of vаlence electrons аs Arsenic with both of them hаving 5 vаlence electrons.
Krypton is а noble gаs locаted in group VIII А аnd 4rd period. Nitrogen is in the 5fh group. So, we must look for аn element locаted in the 4rd period аnd group VА on the periodic table.
Iron (Fe) ⇒ Iron is in the 4rd period аnd group VIBSelenium (Se) ⇒ Selenium is in the 4rd period аnd group VIААrsenic (Аs) ⇒ Аrsenic is in the 4rd period аnd group VА аnd group VАCаlcium (Cа) ⇒ Cаlcium is locаted in group 4rd аnd group IIАYour question is incomplete, but most probably your full options were
a. selenium (Se)
b. arsenic (As)
c. iron (Fe)
d. calcium (Ca)
Thus, the correct answer is B.
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A student is investigating the transfer of thermal energy. The student boils a pot water, removes the pot from the burner, and adds ice cubes to the water. Which direction is the thermal energy flowing in this system?.
The direction of Conduction happens via hotter to colder When materials come into contact, their debris collide.
The strength from the quicker-shifting substance is transferred to the slower-shifting substance till they're shifting on the equal speed. Boiling water on a range is an instance of thermal strength. Thermal strength is produced while the atoms and molecules in a substance vibrate quicker because of a upward thrust in temperature.
Thermal energy actions from warmer frame to chillier frame so we realize that during this test water is a warmer frame while ice cubes are chillier frame so the warmth strength will truely actions from warm frame to the frame.
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be sure to answer all parts. (a) calculate the ph of the 0.39 m nh3/ 0.73 m nh4cl buffer system. ph
NH4+ + H2O results in NH3 + H3O+
Ka = (NH3)(H3O+)/(NH4+)
pKa = 9.2
Since the ion in NH4Cl, NH+4, has a pKa of roughly 9.2, we can proceed to compute the pH as follows:
pH is 9.26 plus log(0.39 M0.73 M) = 8.99, while pOH is 4.74 plus log(0.73 M0.39 M) = 5.01.
pH=14−pOH. =14−5.01≈8.99.
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Pressure has little effect on the solubility of liquids and solids because they are almost incompressible. (True or False)
It is true that pressure has little or no impact on the solubility of liquids and solids because they are incompressible.
Pressure is the amount of force applied perpendicularly to an object's surface divided by the surface area across which it is applied. According to Henry's Law, a gas's solubility in a liquid is directly correlated with its pressure above the solution's surface. So the solubility of gas increases with an increase in pressure. The solubility of a solid in a liquid solution is unaffected by pressure changes. This is because liquids barely compress while solids cannot be compressed at all. As a result, pressure has no impact on both.
Therefore, the given statement is true.
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One of the electron transitions in a hydrogen atom produces infrared light with a wavelength of 746. 4 nm. What amount of energy causes this transition?.
The energy of this transition is equal to 4.02 x 10^-19 J.
Calculate the frequency of the light using the equation c = λν, where c is the speed of light (299,792,458 m/s), λ is the wavelength (746.4 nm), and ν is the frequency of the light.
Calculate the energy of the transition using the equation E = hν, where h is Planck's constant (6.626 x 10^-34 J*s) and ν is the frequency of the light.
Calculate the amount of energy caused by the transition by multiplying the energy of the transition by the Avogadro constant (6.022 x 10^23 s^-1).
The amount of energy caused by the transition is 4.02 x 10^-19 J.
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While attempting to determine the structure of a compound using elemental analysis and functional group tests, you are generally able to recover your original sample.a. Trueb. False
While attempting to determine the structure of a compound using elemental analysis and functional group tests you are generally able to recover your original sample as False.
Neutron activation analysis is a commonly used non-destructive analytical method for determining the identity and concentration of elements in a wide variety of materials. The Sodium Test or La Seigne Test is used in elemental analysis to qualitatively determine the presence of foreign elements such as halogens nitrogen sulfur and phosphorus in organic compounds.
Elemental and chemical state compositions are best determined using low information-depth quantitative techniques such as X-ray photoelectron spectroscopy. The most important spectroscopic techniques for structure elucidation are ultraviolet and visible spectroscopy infrared spectroscopy and nuclear magnetic resonance spectroscopy.
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Which is accepted to react most readily with bromine?
It is expected that bromine will react with the Option (D) Propene
CH₃−CH=CH₂ easily.
This is the electrophilic substitution reaction . Alkenes are more reactive than alkanes or alkynes. Additionally, substituted alkenes that release electrons will be more reactive than unsubstituted alkenes.
Alkenes > Alkynes > Alkanes
The choice (A) CH₃−CH₂−CH₃ an alkane will have the lowest level of reactivity to bromine. (C) CH≡CH is an alkyne and will be more reactive than the alkane but less reactive than the alkenes.
Both (B) CH₂=CH₂ and (D) CH₃−CH=CH₂ are alkenes. The electron density on both carbons will be equivalent upon bond breaking in the ethylene molecule (CH₂=CH₂).
In contrast to the ethylene molecule, the substituted carbon atom in the propene molecule (CH₃−CH=CH₂) will have a higher electron density upon bond breaking and a higher reactivity toward the bromine atom.
Therefore, bromine will react more readily with the compound CH₃−CH=CH₂.
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what mass of hydrogen is present in a 200.0 mg sample of water? (hint: calculate percent composition first.)
Mass of hydrogen present in a 200.0 mg sample of water is 22.2g.
The molar weight of water is 18.015 g/mol, and hydrogen has a weight of 1 g/mol.
So mass of hydrogen= (2/18.015)(200)=22.2 grams.
What is hydrogen?
Hydrogen is the first chemical element which is denoted by H. Hydrogen is the lightest element. At trendy conditions hydrogen is a fuel of diatomic molecules having the components H2. it's miles colorless, odorless, tasteless, non-toxic, and enormously flammable.Hydrogen is the maximum ample chemical substance within the universe, constituting kind of 75% of all ordinary dependants.Stars inclusive of the sun are specially composed of hydrogen within the plasma country. most of the hydrogen on this planet exists in molecular bureaucracy including water and organic compounds.To know more about hydrogen, click the link given below:
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What type of bond is formaldehyde?
Formaldehyde has a double bond.
Formaldehyde is a molecule that consists of one carbon atom coma one oxygen atom and two hydrogen atoms.
In this atom carbon and oxygen contains two bonds between them. There is one Bond present between each hydrogen atom and the carbon atom. Generally, the double bonds are shorter than the single bond because a single double s weaken than a single bond.
Because of the presence of the double bond between the carbon and oxygen molecule we can say that formaldehyde as a double bond.
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How much of each starting material would you use to prepare 2. 00 l of each of the following solutions?.
a. For preparing 0.274 M NaOH from 1.00 M NaOH stock solution, add 548 mL of 1.00 M NaOH stock solution to a 2.00 L volumetric flask and b. for preparing 0.120 M K2CrO4 from 1.75 M K2CrO4 stock solution, add 137 mL of 1.75 M K2CrO4 stock solution to a 2.00 L volumetric flask.
A stock solution refers to a solution with a high concentration of a particular solute and is used for obtaining moderate quantities of solute using small volumes. A dilute solution refers to a solution with a low concentration of a particular solute and is used for dealing with substances by using normal volume instead of small volumes.
As the process provided is given by taking a certain volume of a stock solution and adding water to the quantity of solute till it reaches the 2L mark, hence the dilute and stock solution have the same number of moles. The volume (V) of the dilute, which is two liters, and the concentration (M) of the dilute is used to calculate the number of moles of the dilute. The number of moles of the dilute and stock solution are used to calculate how much volume should be taken from it.
The volume taken from the stock solution can be calculated as:
Mstock * Vstock = Mdilute * Vdilute
a. 0.274 M NaOH from 1.00 M NaOH stock solution.
1M * Vstock = 0.274M * 2L
1M * Vstock = 0.548 mol
Vstock = 0.548mol/1M
Vstock = 0.548 L or 548mL
b. 0.120 M K2CrO4 from 1.75 M K2CrO4 stock solution.
1.75M * Vstock = 0.120 M * 2L
1.75M * Vstock = 0.240 mol
Vstock = 0.240mol/1.75M
Vstock = 0.137 L or 137 mL
Note: The question is incomplete. The complete question probably is: Describe how you would prepare 2.00 L for the following solutions: a. 0.274 M NaOH from 1.00 M NaOH stock solution. Add _____ mL of 1.00 M NaOH stock solution to a 2.00 L volumetric flask; fill to the mark with water, mixing several times along the way. B. 0.120 M K2CrO4 from 1.75 M K2CrO4 stock solution. Add _____ mL of 1.75 M K2CrO4 stock solution to a 2.00 L volumetric flask; fill to the mark with water, mixing several times along the way.
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