The balanced equation for the reaction in this experiment is 3CuSO4(aq) + 2Al(s) →→→ Al2(SO4)3 + 3Cu(s) In this experiment, you have seen that exactly 1,99 g copper sulphate is reacted aluminium. When the reaction reaches completion, 0,57 g of copper was collected. Determining the limiting reagent 2.1.1 Calculate the number of moles in 1,99g of copper sulphate.
2.1.2 Calculate the number of moles in 0,254g of aluminium.
2.1.3 Determine the limiting reagent in this reaction. Provide some calculations as well as a justification for your answer
3CuSO4(aq) + 2Al(s) → Al2(SO4)3 + 3Cu(s)
as per the reaction , we can see that in this
3 moles of copper sulphate and 2 moles of aluminium required to make 1 moles of aluminium sulphate and 3 moles of copper
so from this we concluded that copper sulphate is limiting reagent because due to high moles needed it will cause to stop reaction
as in reaction 3 moles copper sulphate requires 480g and 2 mole aluminium requires 54g so here CuSO4 is limiting reaction.
2.1.1) number of moles in 1,99g of copper sulphate.
moles= given mass of substance/ molecular mass of substance
moles= given mass of copper sulphate/ molecular mass of copper sulphate
moles = 1,99g/160g
moles=1.24 moles
2.1.2) number of moles in 0,254g of aluminium.
moles= given mass of aluminium/ molecular mass of aluminium
moles=254g/27
moles=0.40mole
To know more about moles visit : https://brainly.com/question/20486415
#SPJ9
List 4 kinds of hazards that are caused by Volcanoes.
Four kinds of hazards that are caused by the volcanoes are lava flow, floods or tsunami, landslides, and volcanic earthquakes.
Volcanoes emits the hot, dangerous gases, ash, lava, and rocks which can be powerfully destructive. People have been dying from the volcanic blasts. Volcanic eruptions results in the additional menances to the health, such as floods, power outages, water contamination, and wildfires.
Ash exposure can be harmful to infants, elderly people, and people with respiratory conditions such as asthma, emphysema, and other chronic lung diseases.
Hazards such as -
Earthquakes such as preparing for, surviving, and recovering from an earthquake. Floods such as making sure food and water are safe, cleaning up, and emergency supplies. Landslides and Mudslides such as protective measures to take before, during, and after a landslide or debris flow. Power outages such as carbon monoxide poisoning, alternative heat and energy sources, downed power lines, and food and water safety. Wildfires such as smoke inhalation and other wildfire hazards.
Sources
To learn more about volcano hazards,
brainly.com/question/3809876
#SPJ1
What is the number of grams in one mole of(a) hydrogen gas (a diatomic element),(b) helium,(c) carbon monoxide, and(d) water.
Given:
Mole = 1
Formula:
Moles = Given mass / Molar mass
a) Molar mass of hydrogen = 2.016
Mass = 1 * 2.016
Mass = 2.02g
b)Molar mass of Helium = 4
Mass = 1 * 4
Mass = 4g
c)Molar mass of carbon monooxide = 28
Mass = 1 * 28
Mass = 28g
d)Molar mass of water = 18
Mass = 1 * 18
Mass = 18g
The substance's intense property, the molar mass, is independent of the sample's size. The coherent unit of molar mass in the SI is kilograms per mole (kg/mol). Molar masses are, however, virtually generally given in g/mol due to historical considerations.
To learn more about Molar mass click the given link
https://brainly.com/question/15476873
#SPJ4
An aqueous solution contains two species, a and b. the absorbance at 300 nm is 0.372, and at 250 nm is 0.478. the molar absorptivities of a and b are:________
The absorbance at 300 nm is 0.372 and at 250 nm is 0.478. The molar absorptivities of A and B are as follows: A: ε300= 3.22x104 L mol-1cm-1 ε250= 4.05x104 L mol.
What is molarity?Molar concentration, also known as molarity, quantity concentration, or substance concentration, is a unit used to describe the amount of a substance in a solution expressed as a percentage of its volume. The number of moles per liter, denoted by the unit symbol mol/L or mol/dm3 in SI units, is the most often used unit denoting molarity in chemistry. One mol/L of a solution's concentration is referred to as one molar, or 1 M.
Because the volume of most solutions very minimally changes with temperature owing to thermal expansion, using molar concentration in thermodynamics is frequently not practical. Usually, incorporating temperature adjustment factors or utilizing a temperature-independent metric will fix this issue.
To learn more about molarity from the given link:
https://brainly.com/question/26873446
#SPJ4
A student is trying to classify an unidentified, solid gray material as a metal or a nonmetal. Which question will best help the student classify the material?
In order to help the learner categorize the material, the following inquiry is best:" Is the material malleable or ductile?".
What is a malleable material?
Any substance that can be easily hammered into a thin sheet is bendable. The metal that is most malleable is gold. In contrast, ductility refers to a solid material's capacity to deform when subjected to tensile stress.
A ductile substance is what?
The capacity of a material to be hammered thin or stretched into wire without breaking is known as its ductility. You can draw a ductile material into a wire. The majority of metals, including gold, silver, copper, erbium, terbium, and samarium, are excellent examples of ductile materials.
To learn more about physical properties of materials click on the link below:
https://brainly.com/question/1348773
#SPJ9
Questions:
A student is trying to classify an unidentified, solid gray material as a metal or a nonmetal. Which question will best help the student classify the material? A. Is the material malleable or ductile? B. Does the material feel hard to the touch? C. Will the material float in water? D. Does the material feel rough or smooth?
Look at the image. The velocity between point A and point B is
m/s. Only use one decimal point. (3.0, 1.2, 0.9, etc.)
The velocity between point A and point B is 1.0 m/s
How to determine the velocity between point A and point B
What is velocity?
Velocity is simply defined as the rate of change of displacement with time. Mathematically, it can be expressed as:
Velocity = Change of displacement / time
From the question given above, the following data were obtained:
Displacement at A = 0 mDisplacement at B = 8 mChange of displacement = 8 - 0 = 8 mTime at A = 0 sTime at B = 8 sChange in time = 8 - 0 = 8 s Velocity =?The velocity between point A and point B can be obtained as follow:
Velocity = Change of displacement / time
Velocity = 8 / 8
Velocity = 1.0 m/s
Thus, the velocity between point A and point B is 1.0 m/s
Learn more about velocity:
https://brainly.com/question/3411682
#SPJ1
colligative properties are properties of a solution that depend only on the of solute particles in a given volume of solution, not on their .
Colligative properties are properties of a solution that depend only on the number of solute particles in a given volume of solution, not on their type.
What are Colligative properties?
Colligative properties of solutions are characteristics that depend on the quantity of molecules or ions in the solute, but not on the kind of solute. Osmotic pressure, boiling point elevation, freezing point depression, and vapor pressure reduction are examples of Colligative properties.
A property of a solution is said to be collative if it depends simply on the proportion of solute to solvent particles in the solution and not on the nature of the solute.
To learn more about Colligative properties click on the link below:
https://brainly.com/question/1831338
#SPJ4
claudia performed a flame test in her lab. the result of her flame test is shown here. what scientific questions could claudia ask about the flame? check all that apply. what element causes this flame color? is this the prettiest flame color? will the flame color change if another element is added? will changing the temperature affect the flame color? which flame test does the class like the best?
Claudia performed a flame test in her lab, different element causes different flame color, prettiest flame color means it is blue color flame, each element has different amount of extra energy, different part of flame have different temperature, blue color flame test class like the best.
Flame test means the method in which identify of unknown metal and metalloids ion on their characteristics and color which are come on heat on the Bunsen burner called flame test.
Here Claudia performed a flame test in her lab and in that flame test the scientific question could she ask that is and answer of this questions are as follow : different element causes different flame colour because each individual element had its own identity that's why different element causes different flame colour. prettiest flame color means it is blue colour flame this blue colour is so pretty to see in bunsen burner, each element has different amount of extra energy because when heated electron get excited and move to a diffrent orbit and as they cool down they move back to thier normal position and this extra energy produce light waves, different part of flame have different temperature, because different temperature take different colour on the flame like colder part show diffusion and flame will be red in this way, blue or orange colour test are like the class most because it seen so pretty on the bunsen burner.
Know more about flame test
https://brainly.com/question/28535459
#SPJ4
What is a theory?
Group of answer choices
another word for hypothesis
an educated guess
a possible explanation of a general principle offered to explain observed facts
a possible explanation for a hypothesis
An explanation for a natural occurrence is provided by a hypothesis, which is supported by observation and testing.
A hypothesis is a well-informed prediction based on specific data that serves as the basis for more research.
Many of them dismiss evolution as "simply a hypothesis," in contrast to gravity, which must exist because it is a law. In the scientific community, the terms "theory," "facts," "laws," and "hypothesis" have extremely particular meanings that don't quite correspond to the ones we use in ordinary language. A testable hypothesis is a speculative explanation for an observable. It serves as a springboard for additional explanation. Contrarily, a theory is an explanation of a particular feature of the natural world that is supported by facts, validated hypotheses, and rules.
Learn more about hypothesis here:
https://brainly.com/question/17173491
#SPJ9
0.054619 + 0.363792 + 0.217056 = ? round the answer and sig fig
Answer:
0.64
Explanation:
In the preparation of primary amines, how can direct nucleophilic substitution between nh3 and alkyl halide be made more practical than reacting nh3 and the alkyl halide in a 1:1 ratio?
Direct nucleophilic substitution between NH₃ and alkyl halide be made more practical than reacting NH₃ and the alkyl halide in a 1:1 ratio By Using a large excess of NH₃.
Why is direct nucleophilic substitution of an haloalkane with NH₃ not a very useful method for preparing primary amines?
Polyalkylation of the amine will end in multiple products
What happens when haloalkane reacts with NH₃?Ch₂₂: RX + NH₃. Ammonia reacts as a nucleophile with alkyl halides to offer primary amines in a nucleophilic substitution reaction. Yields are often poor because the product, a primary amine, RNH₂, is itself a nucleophile and may react with more alkyl halide.
Is NH₃ a robust nucleophile?
NH₃(Ammonia) has the stronger nucleophilic character than water molecule. Because the Oxygen within the water molecule doesn't likely to bond with any carbon atom compared to Nitrogen atom. Since Oxygen has more electronegativity than Nitrogen. Hence it holds onto its lone pair tightly than Nitrogen.
Learn more about substitution reaction :
brainly.com/question/10143438
#SPJ4
a cell containing only pure water is placed into a solution containing 1m sucrose. the cell's membrane is impermeable to water, sucrose, sodium ions and chloride ions. how could you make the cell isosmotic to the outside solution?
Cell containing pure water with membrane impermeable to water, sucrose, sodium ions and chloride ions can't be made isosmotic to a solution of 1m sucrose.
Osmolarity represents the total amount or concentration of solute in a solution. Solution with low osmolarity means the solution has less solute particles, while solution with high osmolarity has more solute particles. Solution with low osmolarity is referred as hypoosmotic and solution with high osmolarity is referred as hyperosmotic.
When a cell is kept in a solution, the ability of the extra cellular solution to move the water across the cell membrane is called tonicity. Water move from low concentration of solute to high concentration of solute. Water move out of cell if it is kept in hypertonic solution, while water move inside the cell if it is kept in hypotonic solution. The water keeps moving across the membrane until the concentration outside and inside the cell become equal. If cell is placed in an an isotonic solution, the net flow of water is zero.
Impermeable membranes hinders the movement of substance through them. Membrane impermeable to water will not allow the movement of water through it.
to know more about osmolarity
https://brainly.com/question/13597129
#SJ4
What state
of matter has a defined volume but undefined shape?
why is it important to know what substances you have available to work with, and how they might change when you developing special effects
Editing and VFX software has advanced to the point where the only limitations are your technical skills and your imagination
Although they are distinct, special effects and visual effects are frequently confused. There are further categories, however special effects are frequently manufactured artificially on set and are known as practical effects (for example, a controlled explosion in an action scene). On the other side, visual effects are produced in the editing room or post-production. While modern visual effects deal with animation, computer generated imagery (CGI), and other post-production effects, early visual effects saw filmmakers experimenting with film stock.
Each has advantages and disadvantages. According to filmmaker Steven Bernstein, special effects are frequently preferable because they allow actors to react to the effects in real time. They also provide lighting effects and other characteristics that would otherwise need expensive computer creation.
To learn more about special effects please visit-
https://brainly.com/question/11799347
#SPJ9
which of the following sentences is the correct way to answer the following question te gusta ir a la escuela
The correct way to answer
Spanish Ques; te gusta ir a la escuela?
Ans; si, me gusta ir a la escuela.
English Ques; You like go to school?
Ans; I enjoy going to school.
Where spanish language is spoken?
Along with Spain in Europe and Equatorial Guinea in Africa, Spanish is the official language of 18 nations in the Americas (Venezuela, El Salvador, Ecuador, Bolivia, Chile, Colombia, Costa Rica, Cuba, Dominican Republic, Mexico, Nicaragua, Panama, Paraguay, and Uruguay.)
Twenty different countries have made Spanish their official language.
To learn more about Spanish click the given link
https://brainly.com/question/1402616
#SPJ4
What are some examples of chemistry?
plisss
creo que es fermentacion
Answer:
Es Fermentación
iron undergoes an allotropic transformation at 912°c: upon heating from a bcc (???? phase) to an fcc (???? phase). accompanying this transformation is a change in the atomic radius of fe—from rbcc
When iron undergoes an allotropic transformation at 912°c: upon heating from a bcc to an fcc , accompanying this transformation is a change in the atomic radius of fe—from 0.4330a to 0.353a, where a is the edge length of the cubic unit cell.
What is latent heat?The heat energy required for the change of phase of any substance is known as latent heat of that substance for a particular change of phase or process.
Iron changes from a bcc to an fcc at 912 °C, and this allotropic transformation is accompanied by a shift in the atomic radius of fe from 0.4330 a to 0.353 a, where an is the edge length of the cubic unit cell.
Thus, there would be a shift in the atomic radius of iron from 0.4330 a to 0.353 a.
To learn more about Latent heat from here, refer to the link;
brainly.com/question/13428994
#SPJ4
Whta is a major difference between the rutherford and the wave mechnaical models of the atom?
A major difference between the Rutherford atomic model and the Wave mechanical model of atom is that Rutherford model was based on the gold foil experiment which considered only the particle properties of atoms whereas the wave mechanical model considers the particle properties and the wave properties of atoms.
Rutherford atomic model was given by Ernest Rutherford to explain what an atom is. His gold foil experiment showed that atom is mostly empty space with, small, dense, positively-charged nucleus.
Wave mechanical model was given by Thomas Young. He called the experiment as Double-slit experiment, to test the nature of the light. Young discovered that electrons of the atom exhibited the particle-wave dual properties which led to this theory named as wave mechanical theory of an atom.
These theories explain different properties of atoms with the help of different experiments.
To learn more about Rutherford model of atom,
brainly.com/question/2031894
#SPJ4
To get the most reliable temperature measurment, a thermometer should be placed ?
A thermometer should always be submerged in a substance just deep enough to completely cover the bulb in order to measure temperatures accurately.
What is thermometer?An instrument known as a thermometer is used to measure temperature or a temperature gradient. A thermometer consists of two key components: a temperature sensor that changes in response to changes in temperature and a way to translate these changes into a numerical value.
An instrument that measures temperature is a thermometer. It is able to gauge the temperature of solids like food, liquids like water, and gases like air.
to learn more about thermometer go to -
https://brainly.com/question/2339046
#SPJ4
while pipetting diiodoacetic acid, a few droplets landed onto my arm. i washed it off for 15 minutes and did not see any sign of a chemical burn on my skin. i should proceed to do the following: 1 point
If you washed it off for 15 minutes and did not see any sign of a chemical burn on your skin , you can: visit a doctor if you see any sign on your skin.
Steps to follow in case of acid dropped on skin:
Immediately run lukewarm water over the area for 30 minutes.Remove any jewelry and clothing from the afflicted region.Watch for symptoms to develop. After 20 to 30 minutes, if the burning feeling on your skin is still there, keep rinsing under a stream of clean water and call your doctor or the Poison Control Hotline.What is Diiodoacetic acid?
A disinfection by-product (DBP) created during the disinfection of water is Diiodoacetic acid. Asparagopsis taxiformis contains the natural substance diiodoacetic acid, according to accessible information.
Iodoacetic acid: What is it?
A byproduct of acetic acid is iodoacetic acid. Because it is an alkylating agent, like many alkyl halides, this substance is poisonous.
To learn more Iodoacetic acid click below-
https://brainly.com/question/22575818
#SPJ4
Which isotope has a longer half-life? select the correct answer and explanation.
Xenon-124 isotope has a longer half life.
The duration needed for a quantity to decrease to half of its initial value is known as the half-life.One of those isotopes whose half life are longer is xenon 124, whose half-life has been calculated by experts to be 18 sextillion years due to its disintegration into tellurium 124.Half-life does not imply that atoms degrade at a constant rate. The figure simply represents the time it will take, on average, for the majority of a radioactive element to diminish itself by half.While the majority of xenon isotopes have half-lives of less than 12 days, Xenon-124 is believed to have extraordinarily long half-lives and to be fundamentally stable.These decays, which are the rarest processes ever directly recorded, have been detected in the XENON1T detector in 2019.Thus Xenon-124 has highest half life.
Learn more about half life here:
https://brainly.com/question/13979590
#SPJ4
what happens to a cysteine residue whose side chain was previously a free thiol when you treat it with dtt
Cysteine is an amino acids.
Used to making proteins and functions is to create metabolism.
thiol (-SH) is the side chain of cysteine residue.
thiol (-SH) often works in the agile site of enzymes. In protein molecules, two cysteine residues frequently make a disulphide bond, which is important in folding the proteins and balancing their structure.
When it free thiol (which is residue of cystine) is treat with dtt the important role of DTT in molecular biological test is to hold on to the proteins in a lower condition. Dtt is soluble in ethanol.
DTT can react with proteins without the help of cystine residue and that comes under biochemical reactivity.
To know more about Cysteine here :
https://brainly.com/question/14835777?referrer=searchResults
#SPJ4
Hazardous gas released from a factory’s smokestack is an example of __________ externality. a. local b. positive c. resource d. negative
Answer: D. negative
Explanation:
classify each reactant and product in this reaction as an acid or base according to the brønsted theory. hf h2o↽−−⇀f− h3o
Bronsted-lowry theory does not define acid and bases particularly but they particularly tell how they react or act in the given chemical reaction.
Bronsted-Lowry theory are also known as proton theory of acids and bases.
From the given reaction, HF contribute a proton, in the form of an H+ atom, to water H2O, producing the fluoride F− and hydronium H3O+ ions. The reactant side of Bronsted-Lowry acid is :
Bronsted−Lowry acid: HF
On the other hand the Bronsted-Lowry base is
Bronsted−Lowry base : H2O
Meanwhile, the particle on the product side that same after the Bronsted-Lowry acid contribute a proton to the Bronsted-Lowry base is called a conjugate base (are able to take a proton) while the persist particles taking a proton is the conjugate acid (are able to contribute a proton). Hence,
Bronsted−Lowry acid : H3O + Bronsted−Lowry base : F−
To know more about Bronsted - Lowry Theory here :
https://brainly.com/question/27724955?referrer=searchResults
#SPJ4
arene and functionalized arene based two dimensional organic-inorganic hybrid perovskites for photovoltaic applications
Our study reveals that both the perovskites are direct band gap semiconductors and possess desirable band gap for solar energy absorption.
What is perovskites?Calcium titanium oxide mineral perovskite is made up of calcium titanate and has the pronunciation /prvskat/. (chemical formula CaTiO3). The perovskite crystal structure, which is the same as that of CaTiO3 (XIIA2+VIB4+X23), is the name given to the group of substances that share this structure. A wide range of tailored materials can be created by embedding numerous different cations in this framework.
It was named after Russian mineralogist Lev Perovski after being found in the Ural Mountains of Russia by Gustav Rose in 1839. (1792–1856).
Victor Goldschmidt's study on tolerance factors from 1926 is where the noteworthy crystal structure of perovskite was first discovered. X-ray diffraction data on barium titanate by Helen Megaw led to the publication of the crystal structure in 1945.
To learn more about perovskites from the given link:
https://brainly.com/question/21299853
#SPJ4
15.91 kilometers to meters
Answer: 15910 meters
Explanation:
1 kilometer = 1000 meters
15.91 kilometers * 1000 meters/1 kilometer =
15.91 * 1000/1=
15.91*1000=15910 meters
given that the density of mercury is 13.6 g/mL, and a sample is 4.2 cm^3, what is the mass of the sample?
I don't understand how to figure this out, so a step by step explanation would be great. Thanks!
Answer:
5.712g
Explanation:
density =mass÷volume
13.6g/mL=mass÷4.2cm^3
mass=13.6×4.2
mass=5.712g
A grignard synthesis begins with 6.00 g of bromobenzene and ends with 3.94 g benzoic acid. what is the percent yield of the benzoic acid? assume all other reagents are in excess.
6.00 g of bromobenzene and 3.94 g of benzoic acid are used in a grignard synthesis. 84.4% of the yield of benzoic acid is produced.
Given:
Grignard synthesis begins with
Bromobenzene = 6 g
to Benzoic acid = 3.94 g
122 g of benzoic acid would be generated from 157 g of bromobenzene.
As a result, 6 g of bromobenzene will result in
Then,
= 122 / 157 × 6
= 4.66g
3.94 is prepared then,
The percentage will be
(3.94/4.66) x 100 = 84.4 percent
An organomagnesium halide with the formula RMgX is a Grignard reagent, and in it, X is a halogen (-Cl, -Br, or -I), and R is an alkyl or aryl group (based on a benzene ring) group. A Grignard reagent is used to start a Grignard reaction, which produces a secondary or tertiary alcohol from a ketone or aldehyde.
To learn more about Grignard reagent click the givne link
https://brainly.com/question/26388782
#SPJ4
what mass of ammonium thiocyanate must be used if it is to react completely with 6.7 g barium hydroxide octahydrate?
Mass of ammonium thiocyanate must be used if it is to react completely with 6.7 g barium hydroxide octahydrate is 3.14g.
What is ammonium thiocyanate?Ammonium thiocyanate is an inorganic compound with formula NH4SCN. It is salt of the ammonium cation and the thiocyanate anion.
Ammonium thiocyanate is used in manufacture of herbicides, thiourea, and transparent artificial resins; in matches; as a stabilizing agent in photography; in various rustproofing compositions; as adjuvant in textile dyeing and printing; as a tracer in oil fields; in separation of hafnium from zirconium (important for the production of hafnium-free zircalloy for use in nuclear fuel cladding), and in titrimetric analyses.
Ammonium thiocyanate can also be used to determine iron content in soft drinks by colorimetry.
Ammonium thiocyanate may also be used to separate the quinidine, from liquors, after the isolation of quinine from the neutral, aqueous, sulphate solution. The salt is added to hot solution and the gummy solid that forms is strained off from the liquid. The solid is then refluxed with methanol, which dissolves most of mpurities, leaving the quinidine thiocyanate as a crystalline solid of 90 - 95% purity. Following the separation, (usually by centrifuge) the solid may then be further purified to pharmaceutical quality. (Quinidine is used for treatment of heart arrhythmia and therefore has considerable value.)
Ammonium thiocyanate = NH4SCN
Barium hydroxide octahydrate = Ba(OH)2 · 8H2O
Solution:
The Balanced chemical equation:
2NH4SCN + Ba(OH)2 · 8H2O → Ba(SCN)2 + 2NH3 + 10H2O
According to equation above: n[NH4SCN]/2 = n[Ba(OH)2 · 8H2O]
Molar mass of Ba(OH)2 · 8H2O is 315.46 g/mol.
Hence,
n[Ba(OH)2 · 8H2O] = (6.5 g) × (1 mol / 315.46 g) = 0.020605 mol
n[NH4SCN] = 2 × n[Ba(OH)2 · 8H2O] = 2 × 0.020605 mol = 0.04121 mol
Molar mass of NH4SCN is 76.122 g/mol.
Hence, mass of NH4SCN will be:
m(NH4SCN) = (0.04121 mol NH4SCN) × (76.122 g NH4SCN / 1 mol NH4SCN) = 3.137 g NH4SCN
Mass of the NH4SCN = 3.137 g = 3.14 g
To know more about barium hydroxide octahydrate visit: https://brainly.com/question/14400390
#SPJ4
Phosphorus-32 has a half-life of 14.0 daysdays. starting with 2.00 gg of 32p32p, how many grams will remain after 112 daysdays pearson?
By the half-life of radioactive, the remaining mass of radioactive elements is 7.8125 x 10¯³ gram.
We need to know about the half-life of the radioactive elements to solve this problem. The radioactive element will decay over time and follow the equation
N = No(1/2)^(t/t'')
where N is the final quantity, No is the initial quantity, λ is the decaying constant, t is time and t'' is the half-life of a radioactive element.
From the question above, we know that
t'' = 14 days
No = 2 grams
t = 112 days
Calculate the remaining mass
N = No(1/2)^(t/t'')
N = 2(1/2)^(112 / 14)
N = 7.8125 x 10¯³ gram
Find more on half-life at: https://brainly.com/question/25750315
#SPJ4
How much 5.70 m naoh must be added to 670.0 ml of a buffer that is 0.0200 m acetic acid and 0.0260 m sodium acetate to raise the ph to 5.75?
Volume is:
0.009524 moles of NaOH x (1L / 5.80mol) = 1.64 x 10⁻³L = 1.64 mL of 5.80 M are added
Moles acetic acid and sodium acetate:Acetic acid: 0.550L x (0.0215mol/L) = 0.011825 moles
Acetate: 0.550L x (0.0255mol/L) = 0.014025 moles
Total no. of moles = 0.025 moles = [ Acetate ] + [ Acetic acid ] (1)
H-H equation:
pH = p Ka + log [ Acetate ] / [ Acetic acid ]
Where pH is 5.75;
pKa of acetic acid is 4.74 ;
5.75=4.74 + log[Acetate] /[Acetic acid]
10.2329 = [Acetate] / [Acetic acid] (2)
Replacing (1) in (2):
10.2329 = 0.02585 - [Acetic acid]/[Acetic acid]
10.23 [Acetic acid] = 0.025 - [Acetic acid]
11.2329 [Acetic acid] = 0.02585
[Acetic acid]= 0.002301 moles.
Moles acetate:
[Acetate]=0.025 moles -0.0023 moles =0.0235 moles
Initial moles 0.0140 moles, and moles of acetate added are:
0.0235 moles - 0.0140 moles = 0.0095 moles of NaOH
1.64mL of 5.80M are added
To learn more about Acetic acid visit the link
https://brainly.com/question/12924347
#SPJ4