Answers
The mass of the materials used in making sparklers is determined by the mole ratio of the reactants in the chemical reactions that occur.
What are sparklers?Sparklers are a kind of fireworks that do not explode but rather sparkle when they are lit.
The materials used in sparklers include materials such as:
Fuels such as iron, (Fe), aluminum (Al), or magnesium (Mg).
Oxidizers such as potassium nitrate( KNO₃) and potassium chlorate (KCLO₃).
Colorants that imbue color to the sparklers.
The reaction that occurs in sparklers is a chemical reaction. In sparklers, magnesium, aluminum, and iron each react with oxygen gas. The heat released from the reactions of the metal with oxygen causes the decomposition of the oxidizers such as potassium chlorate to potassium chloride and oxygen gas which is then used for further oxidation of the metals.
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Related Questions
In each box, write the formula of the ionic compound consisting of the positive ion to the left of the box and the negative ion above the box.
Answers
The formula of the ionic compound consisting of the positive ion to the left of the box and the negative ion above the box are as follows:
MgCl₂, MgS, MgF₂, Mg₃N₂, MgO, Mg₃P₂
CsCl, Cs₂S, CsF, Cs₃N, Cs₂O, Cs₃P
CrCl₃, Cr₂S₃, CrF₃, CrN, Cr₂O₃, CrP
NaCl, Na₂S, NaF, Na₃N, Na₂O, Na₃P
ZnCl₂, ZnS, ZnF₂, Zn₃N₂, ZnO, Zn₃P₂
AlCl₃, Al₂S₃, AlF₃, AlN, Al₂O₃, AlP
What are ionic compounds?Ionic compounds are pure substances made up of chemically bound ions. Examples include his binary compounds such as table salt and polyatomic compounds such as sodium sulfate. All ionic compounds form crystal lattices. Ionic compounds are pure substances formed mainly by positive and negative ionic attraction. Compounds are formed mainly by ions, although a small amount of electron sharing always occurs.
Ionic compounds are pure substances formed from chemically bound ions. Ionic bonds form ionic compounds. Covalent bonds form molecular bonds.Most atoms connect through covalent bonds, in which shared electrons form directional bonds. These are molecules.Ionic compounds are electrically neutral and consist of a few atoms (ions) or many atoms (ions). Diatomic and polyatomic compounds are equally common.To know more about ionic compounds, visit:
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Find the number of grams in a 1.25 M solution of potassium nitrate (NO3) if we have
160 ml of the solution.
Answers
Answer:
12.4 g
Explanation:
M=1.25M
v=0.16L
molar mass = 62 g per mole
M=n/v
n=M*v
n=1.25M*0.16
n=0.2moln=mass of a substance /molar massmass of substance = n * M
m=0.2mole *62 g/mole
m=12.4g
____ measures the _____ released when an isolated atom ______ an electron to form a _____ ion. ____ measures the ____ of the atom to hold on to its own electrons and attract electrons from other atoms in compounds. 1.ability2.1-3.1+4.heat5.potential6.gains7.energy8.loses9.The electronegativity10.Electron affinity
Answers
The text to complete refers to electronegativity and electron affinity.
Completed sentence about electronegativity and electron affinityThe electronegativity measures the energy released when an isolated atom loses an electron to form a potential ion. Electron affinity measures the ability of the atom to retain its own electrons and to attract electrons from other atoms in compounds.
Both expressions are part of the atonic energy, that is, the energy contained in the nucleus of the atom and considered one of the largest.
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After considering the results of the classification tests, the possibilities can be narrowed down further by determining the melting point of the
A derivative.
B Schiff addition product.
C iodoform.
D triiodo compound.
Answers
After considering the results of the classification tests, the possibilities can be narrowed down further by determining the melting point of the B Schiff addition product.
What two facts can you infer about your product based on its melting point range?
A compound's melting point is helpful in two ways: it provides information on the composition's identity and degree of purity. Impurities will affect a compound's melting point, resulting in broader and lower melting point ranges.
First, the solubility test must be performed in order to remove soluble contaminants from the target molecule. The desired chemical and the soluble impurities are dissolved in a minimum of near or boiling solvent once a suitable solvent has been selected. The solution is then given time to gradually cool.
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Pretest: Unit 2
Question 15 of 34
Which of the following increases the H* concentration in solution?
A. Water
B. A base
C. An acid
O D. Salt
SUBMIT
Answers
what is the equation for the equilibrium constant of 2 CrO 4 2 − (aq) + 2 H + (aq) ⇌ Cr 2 O 7 2 − (aq) + H 2 O (l)
Answers
The equation for the equilibrium constant K = [ Cr₂O₇²⁻] [ H₂O ] / [ Cr₂O₇²⁻ ]² [ H⁺]².
What is equilibrium constant ?For a chemical reaction, the equilibrium constant can be defined as the ratio of reactant to product that is used to determine chemical behavior. At equilibrium, the forward reaction rate equals the backward reaction rate.
Equilibrium constants vary with temperature and are unaffected by reaction quantities, catalysts, or inert materials. Furthermore, it is unaffected by reactant concentrations, pressures, or volumes. In general, the temperature dependence of the equilibrium constant is determined by H of the reaction.
Thus, The equation for the equilibrium constant K = [ Cr₂O₇²⁻] [ H₂O ] / [ Cr₂O₇²⁻ ]² [ H⁺]².
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Which of the following characteristics of K+ channels are important for the selectivity for K+ rather than other ions?
Answers
K+ channels are important because carbonyl groups lining the wall of the pore and can interact with the unsolvated K+ ion, balancing the energy needed to remove the hydration shell.
What is the role of K + ion channels in an action potential?Potassium channels play a role in repolarization of the membrane, which follows membrane depolarization by Na, and in some cases Ca, channels during the action potential; this is necessary for returning the membrane to a negative potential to terminate the action potential signal.
What effect does opening K+ channels have on membrane potential?Opening of K+ channels in cell membranes with resulting increase in K+ conductance, shifts the membrane potential in a hyperpolarizing direction ,the K+ equilibrium potential. Hyperpolarization reduces the opening probability of ion channels involved in membrane depolarization and excitation is minimized.
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In a chromatography experiment, how do you identify the components of an unknown mixture? Select one: O Compare the Re values of the mixture components to the Ry values of pure known compounds. O Combine the mixture with a series of known compounds and observe the color of the dots. O Combine the mixture with multiple known compounds and look for the largest spots. O Compare the color of the mixture spots to the colors of pure known compounds.
Answers
The correct answer is
a. Compare the Re values of the mixture components to the Ry values of pure known compounds.
Chromatography can identify the components of an unknown mixture by comparing the retention time or retention index of the mixture components to that of known compounds.
Retention time is the time it takes for a compound to pass through a chromatographic column, and retention index is a measure of the distance a compound travels through the column compared to a set of reference compounds. Compounds in a mixture can be identified by comparing the retention time or retention index of the mixture components to pure known compounds.
Other techniques that can be used chromatographically to identify unknown mixture components include mass spectrometry, infrared spectroscopy, and nuclear magnetic resonance spectroscopy. These techniques involve analyzing the molecular properties of mixture components to determine their identities.
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The question that I have is in the photo
Answers
Answer: 56.1 g
Explanation:
We begin by finding the formula mass of KCl.
The atomic mass of K is 39 g/mol.The atomic mass of Cl is 35.5 g/mol.So, the formula mass of KCl is [tex]39+35.5=74.5[/tex] g/mol.Therefore, 87.0 grams of KCl is equal to [tex]\frac{87.0}{74.5}=1.167785[/tex] moles.
From the reaction, we know that for every 2 moles of KCl produced, 3 moles of diatomic oxygen are produced. This means that there are [tex]1.167785(3/2)=1.7516775[/tex] moles of diatomic oxygen.
The formula mass of diatomic oxygen is 32 g/mol, meaning [tex](1.7516775)(32)=56.1[/tex] grams of diatomic oxygen were produced.
Consider the kinds of intermolecular forces present in the following compounds, and rank the substances in likely order of decreasing boiling point: H2SH2S (34 amuamu), CH3OHCH3OH (32 amuamu), C2H6C2H6 (30 amuamu), ArAr (40 amuamu).
Answers
In order of decreasing boiling point, CH3OH > H2S > C2H6 > Ar. The strongest types of bonding are ionic, covalent, hydrogen, and van der waals forces, in that order.
Give examples of each of the three forms of intermolecular forces?London dispersion forces (LDF), dipole-dipole interactions, and hydrogen bonds are different intermolecular forces. All substances have LDF, but molecules can have combination of these three types of intermolecular interactions.
What makes dipole-dipole the most powerful?The dipole-dipole forces increase with increasing polarity. Dipole-dipole forces are in an unique (stronger) case in this situation. It is possible for it to exist between a molecule with an N, O, or F atom that has a hydrogen atom bonded to it directly and another molecule with an N, O, or F atom that has a lone pair of electrons.
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18) Jamal performs an experiment where he mixes hydrochloric acid and zinc metal together. He writes a chemical equation that he thinks models his experiment.
2HCl(aq) + Zn(s) - ZnCl₂(aq) + H₂(g)
A) Heat was absorbed
B) A precipitate formed.
The color changed.
D) A gas was formed.
Answers
Answer:
the answer is D.
Label each diagram (A, B, and C) as either convergent plate boundary, divergent plate boundary, or transform plate boundary. three plate boundaries
Answers
Diagram A is a divergent plate boundary, B is a convergent plate boundary and C is a transform plate boundary.
What are tectonic boundaries?Plate tectonics are boundaries between two or more plates moving towards each other, away from each other or past each other. When these occur they are known as either convergent, divergent or transform plate boundaries.
A convergent plate boundary, the tectonic plate converge by subduction, where the thin ocean crust slides beneath thick crust. It is divergent when the linear features are moving away from each other. For transform plate, the broad zone slides northwestward past the north plate.
The full question is:
Label each diagram (A, B, and C) as either convergent plate boundary, divergent plate boundary, or transform plate boundary. three plate boundaries
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according to the spectrochemical series, which of the following ligands has the strongest splitting field?
Answers
The increasing order of the crystal field splitting- I− < Br− < S2− < SCN− < Cl−< N3 < F−< NCO−< OH−<C2O42−< O2−< H2O < acac− < NCS− < CH3CN <gly <py < NH3 < en < bipy < phen < NO2− < PPh3 < CN− < CO.
Describe the spectrochemical sequence.The ligands (affections to a metal ion) are listed in the spectrochemical series according to the strength of their field. The series was created by superimposing various sequences acquired from spectroscopic research because it is impossible to generate the full series by examining complexes with the single metal ion.
Which ligands in the spectrochemical series are strong field ligands?The ligands cyanide and CO are classified as strong-field ligands, whereas the halides are weak-field ligands. Ligands such as water and ammonia are said to create medium field effects.
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for a radical addition reaction involving hbr and propene, sort each reaction step into initiation, propagation and termination steps.
Answers
For a radical addition reaction involving HBr and propene , includes initiation , propagation and termination. the reaction is given as :
CH₃CH=CH₂ + HBr + peroxide ----> CH₃CH₂CH₂Br
1) The steps involves in the initiation steps are :
RO - RO ----> 2RO°
RO° + H- Br ----> ROH + Br°
2) this steps involves the propagation steps are :
CH₃ - CH = CH₂ + Br° ---> CH₃ - CH -CH₂ - Br
CH₃ - °CH - CH₂ - Br + H - Br ----> CH₃ - CH₂ - CH₂ - Br + Br°
3) the termination step include :
Br° + Br° ----> Br - Br
2 CH₃ - °CH - CH₂ - Br ---> CH₃ - CH - CH₂ - Br
|
CH₃ - CH - CH₂ - Br
CH₃ - °CH - CH₂ - Br + Br° ---> CH₃ - CH - CH₂ - Br
|
Br
Thus, the above steps are involved in the radical addition reaction.
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A mixture of gases for the synthesis of ammonia with a mass of 1000.0 g at a temperature of 0 0C and pressure 2 atm occupies a volume of 1000.0 L.
1. Determine the volume fraction of gases in the mixture (in percent).
2. Write the equations for ammonia synthesis reactions in laboratories (3 methods).
3. Give the equation for the reaction of ammonia: a) with metal; b) with a non-metal; c) with metal oxide; d) with acid; e) with salt.
Answers
Answer:
1. or A. : .209%
B. : 1000.0 x .20
Explanation:
A chamber contains equal molar amounts of C₂H₂, CH₄, and H₂. If the total chamber pressure is 5.00 atm, then the partial pressure of C₂H₂ is:
Answers
Answer: 1.67 atm
Explanation:
Since the molar amounts are equal, this means that the partial pressure of acetylene is 1/3 of the total chamber pressure.
1. Identify the anode and the cathode in the following combinations of half-cells. Remember that Ecell Eox + Ered and that Egell must be positive in order to function as a voltaic cell. You may use tables of standard reduction potentials in your text. a) Fe/Fe and Zn/Zn anode cathode b) Ag/Ag' and Sn/Sn c) Zn/Zn*2 and Cu/Cu2 d) Sn/Sn2 and Al/Al 2. Sketch a voltaic cell consisting of lead anode and a copper cathode. Clearly label both electrodes, the voltmeter, salt bridge, the direction of electron flow, and suggest possible salts which could be dissolved in the half cells to complete the cell.3. Give the cell notation for a voltaic cell consisting of a metallic iron anode immersed in a solution of FeCly, and a metallic copper cathode immersed in aqueous Cu(NO3)2.
Answers
a) Fe is the anode and Cu is the cathode. b) Ag is the cathode and Sn is anode c) Zn is anode and Cu is cathode d) Al is cathode and Sn anode.
2. What type of salts are used in the half cells to complete the cell?Possible salts that can be dissolved in half cell to complete the cell : potassium chloride (KCl) and potassium nitrate (KNO3) are better inert salts.
A salt bridge's main function is to maintain electrical neutrality between two beakers and to do so the salt used must be inert. The ions must to move to and forth between the two half cells.
3. Cell notation for a voltaic cell consisting of metallic iron anode immersed in a solution of FeCl3 and a metallic copper cathode immersed in aqueous Cu(NO3)2.
Fe°|Fe3+|| Cu2+|Cu
Left electrode -- anode and right electrode -- cathode.
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Select all of the following amino acids that will create salt-bridges.
Serine
Aspartate
Histidine
Valine
Answers
Among the given amino acids, serine, aspartate and histidine can create protein salt bridges.
How amino acids take part in salt-bridge formation?Two non-covalent interactions—hydrogen bonding and ionic bonding—combine to form a salt bridge. One of the most significant noncovalent forces in chemistry and in biological systems is ion pairing. In a normal acid-base neutralization process, amino acids interact with one another to create salt. Simple attraction between the positive and negative charges and the shift of the -H (positive ion) from the acid to the amine constitute the reaction.
Amino acids that take part in bridge formation are- The anionic carboxylate (RCOO) of either aspartate or glutamate and the cationic ammonium (RNH3+) from lysine or the guanidinium (RNHC(NH2)2+) of arginine most frequently form the salt bridge. Although these are the most frequent, depending on external variables, additional residues with ionizable side chains like histidine, tyrosine, and serine can also take part in salt bridge formation.
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Serine, aspartate, and histidine can build protein salt bridges among the other amino acids mentioned.
How do amino acids contribute to the creation of salt bridges?
A salt bridge is created when two non-covalent interactions—hydrogen bonding and ionic bonding—combine. Ion pairing is one of the most important noncovalent forces in chemistry and in biological systems. Amino acids interact with one another to produce salt during a typical acid-base neutralization process. The reaction is simply the shifting of the -H (positive ion) from the acid to the amine and the attraction of the positive and negative charges.
The anionic carboxylate (RCOO) of either aspartate or glutamate, the cationic ammonium (RNH3+) from lysine, or the guanidinium (RNHC(NH2)2+) from arginine, are the amino acids that participate in bridge building. Although these are the most frequent, salt bridge creation can also involve other residues with ionizable side chains such histidine, tyrosine, and serine depending on the environmental factors.
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Which of the following best demonstratesthat a chemical change has taken place?
The mass of the salt solution, beaker and nails
decreased.
The volume of the salt solution has decreased.
The salt solution was discolored after a week.
The iron nail is still undissolved in the solution
after a week.
Answers
Answer:
the last one
Explanation:
THE IRON NAIL IS STILL UNDISSOLVED IN SOLUTION AFTER A WEEK
Which of the following is not a strong acid? HNO3 HC2H3O2 (aka CH3COOH) All are strong acids. HCI H2SO4
Answers
Which of the following is a hydroxide ion?
Select one:
O a. H*
Ob. H30
O c. (OH)*
O d. 0²-
Answers
Answer:
a
Explanation:
hope this helps for now
Use the gizmo to explore whether the number of atoms present affects the half-life that you measure. describe your findings below:
Answers
In contrast, the ratio and total quantity of stable atoms are defined by the half-life.Whatever the initial number of atoms, the percent of decrease is constant.They can determine the quantity of original carbon-14 by using the carbon-14 half-life of 5,730 years and the ratio of carbon-12 to carbon-14.
What is the rate of change of the radioactive atom number?Since approximately half of the nuclei of each atom decay with each half-life, the number of radioactive atoms falls as the number of half-lives grows.
Amount has an impact on half-life?A longer dose interval will result from a longer half-life, which is reliant on both clearance and volume of distribution. For example, a CYP1A2 or CYP2C19 substrate can cause a decrease in clearance.
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Which of these processes is a chemical change?
Answers
Answer:
Detailed Solution. The correct answer is Photosynthesis in plants. A chemical change takes place when a substance undergoes a chemical change i.e its molecular composition is changed entirely. It involves the formation of new substances and it is a permanent change.how many grams of aluminum chloride AICI3 form when .25 mol AI reacts
Answers
Answer: 333.415 grams of AlCl3
Explanation:
The alkyl halide shown below undergoes an elimination reaction. Select all possible elimination products from the given structures provided below. (1 pts)}
Answers
OPTION A and OPTION D are the possible products from the given structures provided.
Alkyl Halides: What Are They?
Alkyl halides are chemical compounds that are frequently generated from alkanes that include one or more halogens. They are also known as haloalkanes or halogenoalkanes. Alkyl halides are also a part of the larger category of halocarbons.What does alkyl halide mean?
An alkyl halide, as its name indicates, is a hydrocarbon molecule in which halogens stand in for one or more hydrogen atoms. Fluorine, chlorine, bromine, and iodine are among them. R-X, where X is a halogen and R is an alkyl group, is the general structure.What varieties of alkyl are there?
Make sure you understand the definitions of and use for the essential phrases listed below.Alkyl group, methyl group, isobutyl group, sec-butyl group, tert-butyl group, primary carbon, and secondary carbon.To know more about alkyl checkout this link:
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Explain how the interactions between molecules cause the difference in the state of nitrogen and water.
PLEASE I NEED THIS ANSWER ASAP --- DUE MONDAY DEC 5
Answers
The state of matter is dependent on the intermolecular forces of attraction and this is the case of Nitrogen which is gas and has Vander Waal's force of attraction while water, a liquid molecule has hydrogen bonding.
What is the interaction between molecules?Molecular interaction occurs between molecules or atoms which are linked by bonds. These interactions include repulsive and cohesive forces. An interaction is cohesive when the attraction force between molecules are of alike nature. It is repulsive for unlike molecules.
Intermolecular forces are the attractive and repulsive forces between molecules. The presence of Vander Waal's force in Nitrogen and hydrogen bond in water makes it repulsive.
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need answer ASAP PLEASE!!
A container of oxygen gas has a volume of 145.6 L. If the pressure of the gas is
101.3 kPa and the temperature is 0 °C, determine the amount of oxygen gas in the
container. [ans: 6.50 mol]
Answers
According to ideal gas equation, there are 6.49 moles of oxygen gas in the container.
What is ideal gas equation?The ideal gas equation is a equation which is applicable in a hypothetical state of an ideal gas.It is a combination of Boyle's law, Charle's law,Avogadro's law and Gay-Lussac's law . It is given as, PV=nRT where R= gas constant whose value is 8.314.The law has several limitations.The law was proposed by Emile Clapeyron.
Substituting the given values in above equation, n=PV/RT=101.3×145.6/8.314×273.15=6.49 moles.
Thus, there are 6.49 moles in the container.
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Reasoning About Photographing an Eclipse
Reasoning About Photographing an Eclipse
With your group, use the Reasoning Tool to connect each piece of evidence to the claim you think is correct.
Question: When can a lunar eclipse be photographed?
Claim 1: A lunar eclipse can be photographed anytime Earth is in between the sun and the Moon.
Claim 2: A lunar eclipse can be photographed sometimes when Earth is in between the sun and the Moon.
Evidence
This matters because . .
Therefore, . . .
(claim)
Example evidence: two Top View images
A lunar eclipse can be photographed sometimes when Earth is in between the sun and the Moon.
Evidence source: “An Ancient Machine for Predicting Eclipses” article
A lunar eclipse can be photographed sometimes when Earth is in between the sun and the Moon.
Evidence source: Earth, Moon, and Sun Sim
A lunar eclipse can be photographed sometimes when Earth is in between the sun and the Moon.
Evidence source: Moon Sphere Model
A lunar eclipse can be photographed sometimes when Earth is in between the sun and the Moon.
Answers
Therefore, the correct claim is: A lunar eclipse can be photographed sometimes when Earth is in between the sun and the Moon.
What is a Lunar Eclipse?A lunar eclipse occurs when Earth is positioned between the sun and the Moon, blocking the sun's light from reaching the Moon and casting a shadow on it.
However, not every lunar eclipse is visible and can be photographed. The visibility of a lunar eclipse depends on several factors such as the position of the moon in its orbit, the location of the observer on Earth, and the weather conditions.
Hence, the claim "A lunar eclipse can be photographed sometimes when Earth is in between the sun and the Moon" is supported by the evidence provided and is therefore correct.
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Which of the statements about coal is false?
Burning coal causes air pollution.
The waste from burning coal must be stored securely for a very long time.
Mining coal can damage the land and pollute water resources.
Burning coal produces a large amount of energy.
Answers
Burning coal produces a large amount of energy. This statement is false about coal. Therefore, option D is correct.
What is burning coal ?In the United States, coal is primarily used as a fuel to generate electricity. Bituminous coal, subbituminous coal, or lignite are burned in coal-fired power plants. The heat generated by coal combustion is used to convert water into high-pressure steam, which drives a turbine and generates electricity.
Carbon is found in all living things, including humans. When coal is burned, the carbon in the coal combines with the oxygen in the air to form carbon dioxide. Carbon dioxide (CO2) is a colorless and odorless gas, but it is one of several gases in the atmosphere that can trap the earth's heat.
Thus, option D is correct.
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Given a titration reaction, the titrant concentration and volume, and the analyte volume and mass, identify the titrant to analyte stoichiometry
Answers
Given a titration reaction, titrant concentration and volume, the analyte volume and mass, then to identify titrant to analyte stoichiometry : Put the coefficients of each compound in order and simplify if possible.
How do you identify analyte and titrant?During titration, there are two solutions: analyte and the titrant. Analyte is the unknown solution for which you would like to know the concentration or the equilibrium constant. The titrant is the known solution which has a precise and accurate concentration.
The stoichiometric point is the point where an equal amount of acid and base is present to neutralize chemical reaction. Known reagents added to chemical reaction are called titrant and unknown solution is called analyte.
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