7. Digestion takes place in the
Blank containing blank
Answer:
Digestion takes place in the...Mouth? Stomach? Esophagus? Small /Large intestine?
Containing... Saliva? Gastric acid?
Explanation:
what mass of ammonium thiocyanate must be used if it is to react completely with 6.7 g barium hydroxide octahydrate?
3.04 gm of ammonium thiocyanate is used to react completely with a molecular mass of 6.7 gm of barium hydroxide octahydrate.
What is molecular mass?The total atomic masses of all the atoms in a molecule make up its molecular mass. The molecular mass indicates a molecule's mass in relation to the ¹²C atom, whose mass is assumed to be 12. Although molecular mass is a dimensionless number, it is assigned the unit Dalton, also known as the atomic mass unit, to indicate that it is equivalent to 1/12th the mass of a single carbon-12 atom.Although it is often accepted that molecular weight and relative molecular mass are synonymous, in actuality, the two terms are very varied.A weighted average equivalent to the molar mass but with different units is usually employed when the molecular weight is used with the units Da or u.The molecular weight, which is stated in kDa and is used in molecular biology to describe the mass of macromolecules, is frequently imprecise and denotes an average.
Ba(OH)₂.8H₂O + 2NH₄ScN⇒ Ba(ScN)₂ + 10H₂O + 2NH₃
weight = Molecular mass × Number of moles
moles of barium hydroxide octahydrate = 6.5/315 = 0.02 M
moles of ammonium thiocyanate = 2 × 0.02 = 0.04 M
weight of ammonium thiocyanate required = 0.04 × 76.1 = 3.044 gm.
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Suppose it takes 12.69 ml of 0.0026 m i2 solution to reach the end point of the titration. how many moles of vitamin c are present?
Moles of vitamin c are present is 3.299 x 10^-5 mol
Sol:
12.69 mL x 1L/1000mL x 0.0053 M
What is mole?
A fundamental unit of measurement used by chemists is the mole. Chemists use moles to quantify extremely small substances like atoms, molecules, or other particles.
Simply put, a mole is a measuring unit. It's one of the International System of Units' seven foundation units, in reality. Units are created when preexisting ones are insufficient. At the same time that using absolute numbers of atoms, molecules, or ions would be unclear, chemical reactions frequently occur at low concentrations where using grams would be inappropriate.
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1.________data are descriptions and involve characteristics that cannot be counted.
Answer:
c
Explanation:
the mass spectrum for an unknown element is shown above. according to the information in the spectrum, the atomic mass of the unknown element is closest to 90amu 90 a m u 91amu 91 a m u 93amu 93 a m u 94amu
Because 1s electrons are most attracted to the nucleus, peak X results.
For A(27.977 u)
Mass number = 27.977
Abundance = 78.21%
For B (28.976 u)
Mass number = 28.976
Abundance = 1.346%
For C(29.974 u)
Mass number = 29.974
Abundance = 20.444%
Averages atomic mass
= (Mass of A x abundance of A)/100 + (Mass of B x abundance of B)/100 + (Mass of C x abundance of C)/100
= (27.977x78.21)/100 + (28.976x1.346)/100 + (29.974x20.444)/100
= 21.8808117 + 0.39001696 + 6.12788456
= 28.40
What is a nucleus?In terms of genomics, a nucleus is the organelle within a cell that is membrane-enclosed and houses the chromosomes. The nuclear membrane has a variety of pores that enable the selective passage of specific molecules (such proteins and nucleic acids) into and out of the nucleus.
The nucleus carries the genes, structures that hold the genetic information, and controls and regulates the functions of the cell (such as growth and metabolism).Inside the nucleus, tiny structures known as nucleoli are frequently seen. The gel-like matrix in which the nuclear components are suspended is known as the nucleoplasm.
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An analytical chemist has determined by measurements that there are 81. moles of silicon in a sample of talc. how many moles of hydrogen are in the sample? round your answer to 2 significant digits.
The moles of hydrogen in the talc sample are 4.05 moles.
What is analytical chemistry?
Analytical chemistry examines and makes use of the tools and procedures used to classify, distinguish, and measure matter. In actuality, the analysis may consist entirely of separation, identification, or quantification, or it may be supplemented with another technique.
The hydrous silicate minerals include talc. Talc's chemical composition is Mg3Si4O10(OH)2.
There are 3 moles of Mg, 4 moles of Si, 12 moles of O, and 2 moles of H, according to the formula.
A particular SI unit used to measure quantity is the mole.
The answer is that silicon equals 8.1 moles.
Additionally, 4 moles of Si = 2 moles of H
Consequently, moles of H equal 8.1 moles (2 moles of H / 4 moles of Si), making moles of H equal to 4.05 moles.
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If 28.0% of a sample of erbium-165 decays in 4.74 hours, what is the half-life of this isotope (in hours)?
28.0% of a sample of erbium-165 decays in 4.74 hours. The half-life of this isotope (in hours) is 10hr.
What is an isotope?Isotopes are the two or more types of atoms that have the same atomic number (number of protons in their nuclei) and position in the periodic table (and hence belong to same chemical element), and that differ in nucleon numbers (mass numbers) due to different numbers of neutrons in their nuclei. While all the isotopes of a given element have almost the same chemical properties, they have different atomic masses and physical properties.
The number of protons within atom's nucleus is called atomic number and is equal to the number of electrons in the neutral (non-ionized) atom. Each atomic number identifies a specific element, but not isotope; an atom of a given element may have a wide range in its number of neutrons. The number of the nucleons (both protons and neutrons) in the nucleus is the atom's mass number, and each isotope of a given element has a different mass number.
Let us consider initial conc. = [tex]A_{o}[/tex]
final conc. = (100-28)% of [tex]A_{o}[/tex]
according to first order decay law
[tex]At=A_{o} e^{-kt}[/tex], t= time= 4.74hr.
so, 72[tex]A_{o}[/tex]/100 = [tex]A_{o} e^{-4.74k}[/tex]
=1x (72/100) = -4.74k
k = 0.0693
Now, x= 0.693/[tex]t_{1/2}[/tex] , [tex]t_{1/2}[/tex]= half life
putting all the values we can write
0.0693= 0.693/[tex]t_{1/2}[/tex]
[tex]t_{1/2}[/tex]= 10hrs.
so the half life is 10hrs.
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Cranberry juice has a ph of 2.4, while grape juice has a ph of 3.3; which juice has more h ions?
Cranberry juice has more H ions in it as compared to the grape juice. Seven is the neutral pH. An increase in pH above 7 indicates an increase in alkalinity, whereas a fall in pH below 7 indicates an increase in acidity (hydrogen ions) (hydroxyl ions).
The concentration of hydrogen ions, or [H +], is represented by the pH scale, which is a logarithmic scale. In a logarithmic scale, such as the pH scale, a pH shift of 1 equates to a ten-fold change in the concentration of hydrogen ions. A solution with a pH of 5 contains 100 times more hydrogen ions than one with a pH of 7. A pH of 4 has a 1000-fold hydrogen ion concentration, while a pH of 3 has a 10,000-fold concentration.
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The arid and semi-arid regions located poleward of the equator on an idealized supercontinent represent the location of which feature?
The arid and semi-arid regions located poleward of the equator on an idealized supercontinent represent the trade wind feature.
The constant east-to-west predominant winds that blow in the equatorial region of the Earth are known as the trade winds or easterlies. The trade winds are strongest during the winter and when the Arctic oscillation is in its warm phase, and they primarily originate from the northeast in the Northern Hemisphere and the southeast in the Southern Hemisphere.
For generations, sailing ship captains have exploited the trade winds to navigate the world's waters. As it descends, the temperature rises while the moisture content stays constant, lowering the relative humidity of the air mass, making subsident (sinking) air comparatively dry. This hot, dry air is referred to as trade wind.
Usually found above a marine tropical (warm and wet) air mass, this warm, dry air is often referred to as a superior air mass. A temperature inversion is a rise in temperature with height. A trade wind inversion is what it is called when it happens during a trade wind regime.
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Determine the normal stress and shear stress acting on the inclined plane ab. solve the problem using the stress transformation equations. show the results on the sectional element.
The total quantity of cresol solution is q1= 8.25.
What is cresol solution?Cresols (also hydroxytoluene or cresylic acid) are group of aromatic organic compounds. They are the widely-occurring phenols (sometimes called phenolics) which may be either natural or manufactured. They are also categorized as the methyl phenols. Cresols commonly occur as either solids or liquids because their melting points are generally close to the room temperature. Like the other types of phenols, they are slowly oxidized by exposure to air, and the resulting impurities often give the samples a yellow to brownish red tint. Cresols have an odor characteristic to that of the other simple phenols, reminiscent to some of a "coal tar" smell. The name "cresol" is an adduct of the phenol and their traditional source, creosote.
A flavorless, CH3COC6H3(CH3)OH, made from the gualac resin and beechwood tar, it is an active ingredient in creosote and is used as an antibacterial. Word genesis.
total quantity (q2) = 50ml
concentration of final solution
C2 = 1:150
= 1/150* 100
= 0.66%
quantity of stock * concentration of stock= quantity of final solution * concentration of final solution.
q1 * c1= q2 * c2
q1= 50*0.66/4
= 8.25ml
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When acetic acid and sodium bicarbonate react, why does total mass of the beaker contents decrease?
Because carbon dioxide is released during the reaction between acetic acid and sodium bicarbonate, the total mass of the beaker's contents decreases.
What is acetic acid?Acetic acid, systematically named ethanoic acid, is acidic, colorless liquid and organic compound with the chemical formula CH3COOH (also written as CH3CO2H, C2H4O2, or HC2H3O2). Vinegar is at least 4% acetic acid by volume, making the acetic acid the main component of vinegar apart from water and other trace elements.
Acetic acid is second simplest carboxylic acid (after formic acid) and its functional group is methyl. It is an important chemical reagent and industrial chemical, used primarily in production of cellulose acetate for photographic film, polyvinyl acetate for wood glue, and synthetic fibers and fabrics.
In the households, diluted acetic acid is often used in descaling agents. In food industry, acetic acid is controlled by the food additive code E260 as an acidity regulator and as a condiment. In biochemistry, acetyl group, derived from acetic acid, is fundamental to all forms of life. When bound to the coenzyme A, it is central to the metabolism of carbohydrates and fats.
The global demand for the acetic acid is about 6.5 million metric tons per year (t/a), of which approximately 1.5 t/a is met by recycling; the remainder is manufactured from methanol. Vinegar is the mostly dilute acetic acid, often produced by fermentation and subsequent oxidation of ethanol.
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A sample of water has a volume of 560
mL and a mass of 560 g. What is the
density of the water?
Explanation:
density=mass÷volume
density= 560÷560
density= 1 g/mL
what is 26.1 celsius converted to kelvin
Answer:
299.25, or if you round it up 300
Formula to find kelvin: Celsius + 273.15 = Kelvin
Explanation:
Can I have brainliest? It would help me out, if not thanks anyways! Hope this helped and have a nice day :)
A hammer and a feather are dropped from the same height. Imagine that there is no resistance to the objects' motion in air. Which value will be different for the two objects?(1 point)
the time it takes for them to fall
the time it takes for them to fall
the upward push of air resistance
the upward push of air resistance
the velocity of the objects
the velocity of the objects
the gravitational attraction between the Earth and the objects
the gravitational attraction between the Earth and the objects
The value that would be different for the hammer and the feather dropped from the same height is the the upward push of air resistance.
What is gravity?The term gravity has to do with the force that is exerted on a body as a result of its presence in the earth's gravitational field. When an object s falling down, the acceleration due to gravity acts on the object.
We know that irrespective mass, the acceleration due to gravity is the same on all the objects that are on earth. This is because all objects are accelerated to the same extent on the earth's gravitational filed.
Thus, the value that would be different for the hammer and the feather dropped from the same height is the the upward push of air resistance.
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Answer:
The time it takes for them to fall.
Explanation:
I hope it help you.
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caffeine (c8h10n4o2) is the world's most consumed psychoactive drug. it's common name is 1,3,7-trimethylxanthine. it is completely absorbed within 30 to 45 minutes and it effects diminish within about three hours. what is the molarity of a solution that contains 14.1 g of caffeine dissolved in 942 ml of solution? enter to 4 decimal places.
The molarity of a solution that contains 14.1 g of caffeine dissolved in 942 ml of solution is 0.0770 mol/l.
The formula for molarity is,
M = n / V
where, M = molarity of solution
V = volume of solution in litres
where, n = given mass / molar mass
n = 14.1 /194.19
n = 0.0726
So, molarity is
M = 0.0726 / 0.942
M = 0.0770 mol/l
Therefore, molarity of a solution that contains 14.1 g of caffeine dissolved in 942 ml of solution is 0.0770 mol/l.
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Check my answers! This is due in 10 minutes, will give brain!
1. Acrylonitrile and ethyl acetate have the same boiling point: 77.2ºC. In one to two sentences, explain what outcome you would expect if a mixture of these two substances were distilled
My answer: These two substances cannot be separated using distillation. Since both Acrylonitrile and ethyl have the same boiling point.
2. Ribbon diagrams show secondary structures and appear less detailed than other model types. In one to two sentences, give a reason that chemists would use ribbon diagrams. What type of information do they provide?
My answer:
Chemists would use ribbon diagram when wanting to study different types of proteins, this is because ribbon diagrams illustrate proteins very well.
3. In one to two sentences, explain why structural formulars are good for depicting polymers
My answer:
Structural formulas are good for depicting polymers because they are able to explain the properties and structures of the compound. Structural formulas of polymers are also able to show the arrangement of atoms that are within the power.
Chemists prefer the ribbon structures because they clearly elucidate the tertiary structure of proteins
What happens when substances have the same boiling point?The process of distillation depends on the boiling points of the substances The process depends on the fact that substances with different boiling points separate from the mixture at different temperatures.
1) If a mixture of acrylonitrile and ethyl acetate which have the same boiling point of 77.2ºC undergo distillation, there would be o separation as the two substances would be collected at once since they have the same boiling point.
2) We know that a proteins is a macromolecule, they have primary, secondary and tertiary structures. Chemists prefer the ribbon structures because they clearly elucidate the tertiary structure of proteins.
3) The reason why structural formulas are preferable for polymers is that they help us to deduce the properties of the polymer.
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some compounds can be seen under uv light becasue they are inherently fluorescent and usually glow brightly
some compounds are often seen under uv light becasue they are inherently fluorescent and usually glow brightly due to presence of impurities
What are fluorescent compounds?the light that a material emits when exposed to photons of a different wavelength. When exposed to UV radiation, a fluorescent object frequently emits light . The fluorescent properties of some deep sea fish and fireflies are samples of fluorescence in nature.
When a substance passes through fluorescence, it emits light after having absorbed light or other electromagnetic wave . B2 emits a yellow colour while fluorescing. tonic glows blue because it contains quinine. Benzimidazoles, benzothiazoles, coumarins, vitamins like cyanocobalamine, fluorene, and pentacene are samples of fluorescent materials.
Why do compounds glow under UV light?When UV light bounces off objects that contain special substances called phosphors, interesting things happen. Phosphors are substances that emit visible light in response to radiation. Phosphors hit by UV light become excited and naturally fluoresce, or in other words, glow
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How many grams of oxalic acid dihydrate is needed to preapare 500.0 ml of a 0.185m?
11.7 grams of oxalic acid dihydrate is needed to prepare 500.0 ml of a 0.185 M.
The amount of a solute per unit volume of a solution, or the concentration of a chemical species in a solution, is expressed as a solute's molar concentration.
The number of moles per liter, denoted by the unit symbol mol/L or mol/dm³ in SI units, is the most widely used unit for measuring molarity.
500 ml of a 0185 M solution is prepared using x grams of oxalic acid dihydrate.
Oxalic acid dihydrate :- (COOH)₂ . 2H₂O
The molar quantity will be:
500 ml × 10⁻³ L / ml × 0.185 mol / L = 0.0925 mol with respect to oxalic acid dihydrate.
The molar mass of oxalic acid dihydrate (COOH)₂ . 2H₂O is 126.07 g / mol.
Therefore, the grams of the oxalic acid required will be:
= 126.07 g / mol × 0.0925 mol
= 11.661475 grams.
= 11.7 grams
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Volatile chemicals are agents that are able to change easily from a ________ into a ________.
Volatile chemicals are agents that are able to change easily from a liquid into a gas.
What are volatile substances?
In the field of chemistry, "volatile" refers to susbtances which vaporise easily .Volatility can be defined as the measure on how fast the conversion of liquid to gas phase takes place.learn more about volatile substances
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do equal volume of any gas under same temperature and pressure contain equal number of atoms? explain
which of the nonsilicate groups contains minerals that are commonly yellow in color, have a metallic luster, and contain important metal ores?
Sulfides are the non silicate groups contains minerals that are commonly yellow in color, have a metallic luster, and contain important metal ores.
How is metal ore formed?Metallic ores occur in all kinds of rock and some varieties of soil. The metallic minerals are concentrated into rich masses by igneous, hydrothermal, or erosional/weathering processes. Metals like chromium, platinum, nickel, copper, and iron can precipitate as sulfide minerals during a cooling body of magma.
What are the group of silicates?Of the approximately 600 known silicate minerals, only some dozen—a group that includes the feldspars, amphiboles, pyroxenes, micas, olivines, feldspathoids, and zeolites—are significant in rock formation. The silicates, due to their abundance on Earth, constitute the foremost important mineral class.
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There is virtually no matter between the Earth and the Moon, only empty space.
Image courtesy of NASA
Yet the Earth and Moon are able to exert a force on each other because
Answer:
of gravity
Explanation:
lmk if this is wrong
the combustion of one mole of liequid hexane releases 3800kj. when 2.3 g of hexane is combusted in a bomb calorimeter
2.3 g of hexane is combusted in a bomb calorimeter.
What is combustion of hexane?
Hexane also engages in hydrocarbon combustion, forming carbon dioxide when combined with oxygen. The complete combustion of hexane yields the following chemical equation: The burning of hydrocarbons releases heat energy and is an example of an exothermic reaction.
Strong intermolecular interactions make up the non-polar, extremely volatile molecule known as hexane. It burns, releasing carbon dioxide and water as a byproduct.
2C6H14 + 19O2 → 12CO2 + 14H2O
Combustion of 1 mole of hexane releases 3800KJ of energy.
86 g hexane = 1 mole
Thus, 2.3 g hexane = 2.3/86 mole = 0.0267 mole.
Thus combustion of 0.0267 mole of hexane releases 3800*0.0267 KJ energy = 101.46 KJ energy. in a bomb calorimeter.
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the radius of a aluminum atom is 143 pm. how many aluminum atoms would have to be laid side by side to span a distance of 4.23 mm? atoms
the no. of Al atoms required to be laid side by side to make up a distance of 4.23 mm is = 4.23/(2 * 143 * 10^(-9) )
= 14790210 atoms of Al.
What is the radius of an atom?
The atomic radius of an atom is the distance between the centre of the nucleus and the outermost electron in each of its energy shells. Since the border is not a clearly defined physical entity, there are many non-equivalent definitions of atomic radius. The four most popular ways to define atomic radius are van der Waals radius, ionic radius, metallic radius, and covalent radius. Due to the challenges of isolating individual atoms to measure their radii, atomic radii are frequently measured in a chemically bonded state; yet, theoretical calculations are simpler when individual atoms are taken into account.
1 pm = 10^(-9) mm
radius of Al atom = 143 pm = 143 * 10^(-9) mm
Diameter of Al atom = 2 * 143 * 10^(-9) mm
Thus, the no. of Al atoms required to be laid side by side to make up a distance of 4.23 mm is = 4.23/(2 * 143 * 10^(-9) )
= 14790210 atoms of Al.
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a piece of sulfur weighs 227 g. when it was submerged in a graduated cylinder containing 50 ml of water, the level rose to 150 ml. what is the density (g/ml) of the sulfur?
A piece of sulfur weighs 2.27 g. when it was submerged in a graduated cylinder containing 50 ml of water, the level rose to 150 ml.
Mass of the material (m)/Volume of the substance equals a substance's density (d) (v)
= 227/100 g/ml
= 2.27 g/ml of sulfur
What is density?
Density is defined as mass per unit volume for a substance. Density, also referred to as mass per unit volume, is the ratio of mass to volume. It determines the material composition of an object in relation to its volume (cubic metre or cubic centimeter). In essence, density is a measurement of how closely together matter is packed.
Mass of the material (m)/Volume of the substance equals a substance's density (d) (v)
= 227/100 g/ml
= 2.27 g/ml of sulfur
Since the quantity of water increased from 50 to 150 ml when the sulfur was submerged. Therefore, it can be claimed that the sulfur's volume was (150-50)ml, or 100 ml.
Thus, the density of the sulfur is 2.27 g/ml in the end.
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A compound boolean expression created with the _______________ operator is true only if both of its subexpressions are true.
A compound Boolean expression created with the AND operator is true only if both of its subexpressions are true.
A Boolean expression is an expression in which values are either true or false. It is mostly used in programming languages. True and false are denoted by 1 and 0 respectively.
The basic Boolean operators are AND, OR, and NOT. In OR operation, the value is true if either one or the values are true. Not operator also known as negation converts the true value into false and vice versa.
Boolean algebra is the basic fundamental of digital circuits and programming languages.
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In joining two molecules by dehydration synthesis, a(n) ______ group is removed from one molecule and a(n) ______ from the other; a new chemical bond then forms between the molecules.
In joining two molecules by dehydration synthesis, a(n) hydroxyl (-OH) group is removed from one molecule and a(n) hydrogen (H) from the other
Dehydration reactions can be defined as the is the reaction in which a molecule of water is eliminated from the reactant molecule. here dehydration synthesis means the process of combination of two molecules with the elimination of water molecules. that's why hydroxyl (-OH) group is removed from one molecule and hydrogen (H) loses from the other this two functional group are removed and then a new chemical bond then forms between the molecules.
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Which chemical group is most likely to be responsible for an organic molecule behaving as a base? (a) hydroxyl (c) amino (b) carbonyl (d) phosphate
The chemical group which is most likely to be responsible for an orgainc molecule behaving as a base is Amino group.
Amines are the nitrogen containing organic bases. Simple organic molecules such as methylamine, H₃N-CH₃, and ethylamine, H₃N-CH₂CH₃ are the bronsted bases.
Functional group is a group of atoms in molecule which have the different and separate chemical properties. It provide certain characteristics to the molecule. The functional group gets attached to the carbon atom.
Functional groups can behave as a base or an acid. It relies in their structure's ability to accept or to donate the H⁺ ions.
Amino group is represented as :
R \ NH₂ . .Amino group has ability to accept the H⁺ ions from the solution, it forms NH₃⁺.
--NH₂ + H⁺ → NH₃⁺
Therefore, Amino group is most likely to be responsible for an organic molecule behaving as a base.
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Consider a 500. ml buffer that contains 0.12 m hocl and 0.080 m kocl. what is the ph of this buffer if ka (hocl) = 3.5 x 10-8? (hint: remember the henderson-hasselbach eqn)
The pH of this buffer after adding 2.5 ml of 10m KOH to the solution is 7.73
What is the ph of this buffer after adding 2.5 ml of 10m KOH to the solution?The HOCl/KOCl buffer has a pKa of 7.46. We can use the H-H equation to determine the pH of this buffer:
[tex]pH = pKa + log / \frac{[A^{-} ]}{[HA]}[/tex]
[tex]pH = 7.46 + log \frac{ [KOCl] }{[HOCl]}[/tex]
Where [] represents the molarity (or moles) of each compound.
Initial HClO and NaClO moles:
HOCl :-0.500L * (0.12mol / L) = 0.06 moles HOCl
KOCl:- 0.500L * (0.080mol / L) =0.04 moles KOCl
HOCl now reacts with KOH to form KOCl:
[tex]HOCl + KOH ----- > KOCl + H_{2} O[/tex]
The moles of KOH in the reaction are as follows:
[tex]2.5x10^{-3} L * (10mol /L) = 0.025 moles KOH[/tex]
That is, 0.025 moles of HOCl are consumed and 0.025 moles of KOCl are produced after the reaction.
Following the reaction, moles are:
The final moles:
HOCl:- 0.06mol - 0.025mol = 0.035mol HOCl
KOCl :-0.04mol + 0.025mol = 0.065mol KOCl
Replacing in the H-H equation:
[tex]pH = 7.46 + log\frac{ [0.065mol] }{ [0.035mol]}[/tex]
pH = 7.73
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a certain ore is 35.4% nickel by mass. how many kilograms of this ore would you need to dig up to have 55.0 g of nickel?
If a certain ore is 35.4% nickel by mass. To have 55.0 g of nickel, we have to dig up 0.155 kg of this ore.
Mass percent of Nickel = (mass of Nickel/mass oft he ore)×100
= 35.4%
This means that in 100 g of ore we have 35.4 g of nickel.
So, 35.4 g of Nickel is present in = 100 g of the ore
1g of Nickel is present in = 100/35.4 g of the ore
55.0 g of Nickel is present in = (100/35.4) × 55.0 g of the ore
= 155.3 g of the ore
1 g = 1/1000 kg
155.3 g = 155.3/1000 kg
= 0.155 kg
So, we need to dig 0.155 kg of the ore to get 55.0 g of Nickel.
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