Answer:
This means that the pressure would become double of it's initial pressure.
Explanation:
Key statements:
- Constant temperature
- What happens to the pressure of the gas if the volume was
smooshed down to half its original size?
Basically the question is asking about the relationship between pressure and volume at constant temperature. This is given by Boyle's law.
Boyle's law states that the volume of a fixed mass of gas is inversely proportional to it's volume at a fixed temperature.
This is given by;
P1V1 = P2V2
Where;
P1 = Initial pressure
P2 = Final pressure
V1 = Initial Volume
V2 = Final Volume
From the question;
V2 = V1/2
Inserting it into the equation;
P1 V1 = P2 V1/2
Divide all through by V1
P1 = P2 /2
P2 = 2 P1
This means that the pressure would become double of it's initial pressure.
For what mechanistic reason does g1 of lactase first act as a brønsted acid during catalysis?.
Answer: Carboxylation of hydroquinone
HELP PLS PLS PLS ILL MARK U BRAINLIEST
Answer:
2 FeCl3 → 2 Fe + 3 Cl2
Explanation:
2 Fe and 6 Cl on the reactants side, and 2 Fe and 6 Cl on the products side.
what discovery was found by Nels Bohr model of atom ?
Answer:
What was Niels Bohr's most important discovery? Niels Bohr proposed a model of the atom in which the electron was able to occupy only certain orbits around the nucleus. This atomic model was the first to use quantum theory, in that the electrons were limited to specific orbits around the nucleus.
Explanation:
Subjects Of Study: atomic model
Oxygen gas generated in the thermal decomposition of potassium chlorate is collected over water. The volume of gas collected is 0.128 L, at a temperature of 297K and a pressure of 762 mm Hg. The vapour pressure of H2O at 297K is 22.4 torr. What is the mass of oxygen collected?
The mass of oxygen collected from the thermal decomposition of potassium chlorate at a temperature of 297 K and 762 mmHg is 0.16 g
How to determine the mole of oxygen producedWe'll begin by obtaining the number of mole of oxygen gas produced from the reaction. This can be obtained by using the ideal gas equation as illustrated below:
Volume (V) = 0.128 L Temperature (T) = 297 KPressure (P) = 762 – 22.4 = 739.6 mmHgGas constant (R) = 62.363 mmHg.L/Kmol Number of mole (n) =?PV = nRT
739.6 × 0.128 = n × 62.363 × 297
Divide both sides by 62.363 × 297
n = (739.6 × 0.128) / (62.363 × 297)
n = 0.0051 mole
Thus, the number of mole of oxygen gas produced is 0.0051 mole
How to determine the mass of oxygen collectedHaven obtain the number of mole of oxygen gas produced, we can determine the mass of the oxygen produced as follow:'
Mole = 0.0051 moleMolar mass of oxygen gas = 32 g/moleMass of oxygen =?Mole = mass / molar mass
0.0051 = mass of oxygen / 32
Cross multiply
Mass of oxygen = 0.0051 × 32
Mass of oxygen = 0.16 g
Thus, we can conclude that the mass of oxygen gas collected is 0.16 g
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If a 4L solution is 80% concentrated lime juice and 20% water, how much 30% concentrated lime juice must be added so that the concentration of the resulting solution is 50% concentrated lime juice
The volume of 30% concentrated lime juice that must be added to a 4L solution of 80% concentrated lime juice and 20% water is 6 L.
What are mixtures?Mixtures are substances which are formed when two or more substances are physically combined together.
Mixtures are heterogenous in nature and the constituents can be easily separated.
The volume of 30% concentrated lime juice that must be added to a 4L solution of 80% concentrated lime juice and 20% water, so that the concentration of the resulting solution is 50% concentrated lime juice is determined as follows:
Let the volume of 30% lime juice required be x;
total volume of lime juice = 0.3x
For 80% lime juice, volume of lime juice = 0.8 * 4 = 3.2 L
New volume of lime juice = 4 + x
New amount of lime juice added = 3.2 + 0.3x
Also, new amount of lime juice = 0.5 * ( 4 + x)
3.2 + 0.3x = 0.5 * ( 4 + x)
0.2x = 1.2
x = 6 L
In conclusion, the volume to be added is obtained from the percent concentration.
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Which of the following statements about the normal operation of nuclear fission reactors is accurate?
Select one:
a. They release large amounts of chemical pollutants into the air.
b. A small amount of fuel produces a large amount of energy.
c. The nuclear waste is quickly and safely disposed of at the reactor site.
d. The hot water surrounding the reactor core can be used to provide hot water for communities in the area.
Answer:
Explanation:
b
Calculate the freezing point depression for 1 kilogram of sodium chloride (NaCl) in 5 kilograms of
water. The Ky of water is -1.86 °C/m.
[tex]\\ \rm\dashrightarrow \Delta T_f=ik_fm[/tex]
m is molalityMoles of NaCl
1000/2343.4molMolality
43.4/58.68[tex]\\ \rm\dashrightarrow \Delta T_f=i(-1.86)(8.68)[/tex]
[tex]\\ \rm\dashrightarrow \Delta T_f=-16.14i[/tex]
i is vant Hoff factor
For NaCl vant Hoff factor is 2( Actually 1.9)
[tex]\\ \rm\dashrightarrow \Delta T_f=-16.14(2)=-32.28°C[/tex]
Moles of NaCl
[tex]\\ \tt{:}\dashrightarrow \dfrac{1000g}{23g/mol}[/tex]
[tex]\\ \tt{:}\dashrightarrow 43.4mol[/tex]
Find Molality
[tex]\boxed{\sf Molality=\dfrac{Moles\:of\:solute}{Volume \:of\: solution\:in\:kg}}[/tex]
Volume of solution=1kg+5kg=6kg[tex]\\ \tt{:}\dashrightarrow m=\dfrac{43.4}{6}=7.2m[/tex]
Vant Hoff factor
[tex]\\ \tt{:}\dashrightarrow NaCl\longrightarrow Na^++Cl^-[/tex]
i=2Freezing point depression
[tex]\\ \tt{:}\dashrightarrow \Delta T_f=iK_fm[/tex]
[tex]\\ \tt{:}\dashrightarrow \Delta T_f=2(-1.86)(7.2)[/tex]
[tex]\\ \tt{:}\dashrightarrow \Delta T_f=-26.7°C[/tex]
A first-order reaction is 81omplete in 264s. A. What is the half-life for this reaction? b. How long will it take for the reaction to reach 95ompletion?
A first-order reaction is 81omplete in 264s.The half-life for this reaction (i) t 1/2 = =3.465×10 −3 s.to reach 95% Completion = 285 s.
To measure reaction rates, chemists initiate the reaction, measure the concentration of the reactant or product at different times as the reaction progresses,
For a 0-order response, the mathematical expression that may be employed to determine the half of life is: t1/2 = [R]0/2k. For a first-order reaction, the half of-existence is given by: t1/2 = zero.693/ok. For a 2d-order response, the method for the half-life of the response is: 1/okay[R]0
The 1/2-life of a response (t1/2), is the quantity of time needed for a reactant concentration to lower via half of compared to its initial awareness. Its software is used in chemistry and medicine to are expecting the awareness of a substance over time
Half of the lifestyles is the time required for exactly 1/2 of the entities to decay 50%.
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Which halogen or halogen-containing compound is typically used as a form of topical antisepsis?
The halogen or halogen-containing compound is typically used as a form of topical antisepsis will be "iodophor".
Iodine will be employed as an antiseptic in the manner of a tincture of iodine, essentially an alcoholic solution.
Iodophor would be an iodine-containing solution that also contains a solubilizing agent, like povidone or a surfactant. Iodophor would be a common sanitizer in the dairy but also brewing sectors. Generally, a high molecular weight carrier, commonly a polymer, has been polymerized with iodine.
Therefore, the halogen or halogen-containing compound is typically used as a form of topical antisepsis will be "iodophor".
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What is the order in which electrons start filling the orbitals?
a. 1s 2s 2p 3s 3p 4s 3d 4p
b. 1s 2s 2p 3s 3p 3d 4s 4p
c. 1s 2s 2p 3s 4s 3p 3d 4p
d. 1s 2s 2p 3s 4s 4p 3p 3d
e. 1s 2s 2p 3s 4s 3p 4p 3d
a. 1s 2s 2p 3s 3p 4s 3d 4p is the correct option.
This gives the following order to fill the orbit: 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f, 6d, 7p, (8s, 5g, 6f, 7d, 8p, and 9s)
Aufbau's principle states that electrons fill low-energy atomic orbitals before they fill high-energy atomic orbitals. .. By following this rule, you can predict the electron configuration of an atom or ion.
There may be two electrons at the maximum of one orbit. Since the s subplane has only one orbit, it can hold up to two electrons. The p subplane has three orbitals, so it can hold up to six electrons. The d-subplane has five orbitals, so it can hold up to 10 electrons.
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What was the purpose of varying the concentrations of sodium alginate and CaCl2?
To determine how stable the beads are as well ensue the securing of maximum enzymes as well as the retention of their activity.
What is concentration?The concentration of a substance simply means the amount of the substance in solution. Thus we are looking at the amounts of sodium alginate and CaCl2 in the system.
The concentrations of the sodium alginate and CaCl2 is varied in order to determine how stable the beads are as well ensue the securing of maximum enzymes as well as the retention of their activity.
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How many molecules of zinc oxide are there in a 2 kg (2,000 g) sample?
Answer:
1.48 x 10²⁵ molecules ZnO
Explanation:
To find the amount of molecules, you need to (1) convert grams to moles (via molar mass) and then (2) convert moles to molecules (via Avogadro's Number). It is important to arrange the conversions/ratios in a way that allows for the cancellation of units.
Molar Mass (ZnO): 65.380 g/mol + 15.998 g/mol
Molar Mass (ZnO): 81.378 g/mol
Avogadro's Number:
6.022 x 10²³ molecules = 1 mole
2,000 g ZnO 1 mole 6.022 x 10²³ molecules
--------------------- x ----------------- x --------------------------------------- =
81.378 g 1 mole
= 1.48 x 10²⁵ molecules ZnO
Cesium sulfite is formed from the cs cation and the so2−3 anion. What is the correct formula for this compound?
Cesium Sulfite is formed from the Cs cation and the SO₃⁻² anion. The correct formula for this compound is Cs₂SO₃.
What is Cation ?Cations are positively charged ions. It forms when an element lose one or more electrons.
Anions are negatively charged ions. It form when an element gains one or more electrons.
Symbol Cs⁺¹ SO₃⁻²
Valency +1 -2
Formula of the compound is Cs₂SO₃.
Thus from the above conclusion we can say that Cesium Sulfite is formed from the Cs cation and the SO₃⁻² anion. The correct formula for this compound is Cs₂SO₃.
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What is the frequency of an
orange light with a wavelength of 483 nm?
[?] × 10²] Hz
Please explain how to solve as well I’m very confused.
Answer:
6.21 x 10¹⁴ Hz
Explanation:
The frequency can be found using the following equation:
λ = c / f
In this equation,
-----> λ = wavelength (m)
-----> c = speed of light (3.0 x 10⁸ m/s)
-----> f = frequency (Hz)
After converting the wavelength from nm to m, you can plug the given values into the equation and simplify to find the frequency.
483 nm 1 m
--------------- x --------------------- = 4.83 x 10⁻⁷ m
1 x 10⁹ nm
λ = c / f <----- Given equation
4.83 x 10⁻⁷ m = 3.0 x 10⁸ m/s / f <----- Insert values
(4.83 x 10⁻⁷ m) x f = 3.0 x 10⁸ m/s <----- Multiply both sides by f
f = 6.21 x 10¹⁴ Hz <----- Divide both sides by 4.83 x 10⁻⁷
Meteorologists use weather balloons to carry weather instruments high into the atmosphere. when it is first released at earth’s surface, a weather balloon typically appears underinflated. what happens to the balloon’s volume and pressure as it rises into the atmosphere? check all that apply. the pressure in the balloon decreases. the pressure in the balloon increases. the volume of the balloon increases. the volume of the balloon decreases.
the pressure in the balloon decreases- True
the pressure in the balloon increases- False
the volume of the balloon increases- True
the volume of the balloon decreases- False
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Which of the following is an oxidation-reduction reaction?
SO2(g) + H2O(l) Right arrow. H2SO3(aq)
CaCO3(s) Right arrow. CaO(s) + CO2(g)
Ca(OH)2(s) + H2CO3(l) Right arrow. CaCO3(aq) + 2H2O(l)
C6H12O6(s) + 6O2(g) Right arrow. 6CO2(g) + 6H2O(l)
B. The chemical reaction that represents oxidation - reduction reaction is CaCO3(s) → CaO(s) + CO2(g).
Oxidation reduction reaction
In oxidation reduction reaction, the oxidizing agent is reduced while reducing agent is oxidized.
In the chemical equation below;CaCO3(s) → CaO(s) + CO2(g)
Calcium (ca) is oxidized calcium (II) ion while the carbon (IV) oxide is reduced carbon (IV) oxide.
Thus, the chemical reaction that represents oxidation - reduction reaction is CaCO3(s) → CaO(s) + CO2(g).
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Answer: The answer is B
Explanation: on edge
The reaction between calcium carbonate (CaCO3) and HCl produces calcium chloride (CaCl2), carbon dioxide (CO2), and water (H2O).What happens when the concentration of hydrogen chloride (HCl) molecules is doubled in this reaction?
CaCO3 + 2HCl → CaCl2 + CO2 + H2O
When the hydrogen chloride concentration doubles, the number of collisions between the reactants
, which causes the rate of the forward reaction to
.
When the hydrogen chloride concentration doubles, the number of collisions between the reactants becomes increased, which causes the rate of the forward reaction to be faster.
What is the rate of a reaction?The rate of a reaction is how fast a chemical reaction occurs i.e. the conversion of reactants to products.
The rate of a chemical reaction can be influenced by certain factors including the concentration of reactants.
The more the concentration of a reactant, the more the collision between the reactants and hence, the faster the reaction will proceed.
Therefore, when the hydrogen chloride concentration doubles, the number of collisions between the reactants becomes increased, which causes the rate of the forward reaction to be faster
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Answer:1. increases 2. increases
Explanation:
Got it right on plato!
The Venn diagram shown below compares the nuclear reactions in the sun and nuclear power plants.
Picture shows two ovals which overlap in the middle. The oval on the left has the label 'Sun' on top and 'A' within it. The oval on the right has the label 'Nuclear power plants' on top and 'Splitting of atoms' within it. The overlapping portion has the label 'Release of energy' within it.
What process is best described by A?
Destruction of atoms
Fission of atoms
Fusion of atoms
Repulsion of atoms
The process which is best described by "A" in this Venn diagram is: C. fusion of atoms.
What is nuclear fusion?Nuclear fusion can be defined as a type of nuclear reaction that involves joining or combining two (2) smaller nuclei of atoms, so as to form a single heavier nucleus accompanied with the release of energy.
Based on the Venn diagram in the image attached below, we can logically deduce that the process which is best described by "A" is fusion of atoms.
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What is the change in entropy (AS) when a solid substance decomposes and
produces gaseous products?
Entropy directs to the degree of disorderliness in a system. Generally, solids have a greater degree of order when corresponded to gas in which the molecules/particles move randomly in all directions.
The transformation in entropy from solid to gaseous phase is a positive change. Because there is increase disorderliness of the system.
What is entropy definition?
A campfire is an illustration of entropy. The solid wood burns and becomes ash, smoke and gases, all of which applied energy outwards more efficiently than the solid fuel. Ice melting, salt or sugar dissolving, constructing popcorn and boiling water for tea are processed with growing entropy in your kitchen.
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Sulfur has an oxidation number of +6 in which two formulas?
A. SO₂ and SO4²-
B. H₂SO4 and SO₂
C. SO3 and SO4²-
D. HSO4- and S₂03²-
[tex] \sf \blue{B. H_{2}SO4 \: and \: SO_{2}}[/tex]
Explanation:As we know in oxidation, oxygen is added and hydrogen is reduced. And in option B, we can observe that is oxygen added +6. So, we conclude that option B is valid.
Hope it help youWhat substitute for fossil fuel depletion has been heralded as the solution to the nation’s energy problems??
The renewable energies are the substitute for fossil fuel depletion has been heralded as the solution to the nation’s energy problems.
The benefits of renewable energies to the environment and economic are as follows.
The renewable energies produces less global warming.It also reliable and resilience.The renewable energies helps to improve public health.Through renewable energies ,jobs and other economic gets benefits.The prices of renewable energies is stable.The renewable energies is inexhaustible energy.learn about renewable energies
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Calculate and record the expected mass of benzoic acid required to react with 20.00 mL of a 0.100 M sodium hydroxide solution. Record the mass of benzoic acid using three significant digits to reference later.
The mass of benzoic acid is 0.244 g.
Here use the concept of molarity.
What is molarity?The amount of a substance in a specific volume of solution is known as its molarity (M). The moles of a solute per liter of a solution is known as molarity.
Molarity = no. of moles/volume (in L)
Calculation:Given,
Molarity, M = 0.100 M
Volume, V = 20.00 mL = 20.0 × 10⁻³
To calculate,
Mass of benzoic acid C₇H₆O₂ =?
We know that,
Molecular mass of benzoic acid, C₇H₆O₂ = 122
No. of moles = weight/ molecular mass
The formula is modified as,
Molarity = weight of cholesterol/ (molecular mass) (Volume)
Put the values in the formula,
0.100 = Mass of benzoic acid/ (122) (20 × 10⁻³)
Mass of benzoic acid = 0.100 (122)(20 × 10⁻³)
= 244 × 10⁻³
= 0.244 g
Hence, the mass of benzoic acid is 0.244 g.
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Noble gases have __ values of ionization energy due to their complete outermost shells
Answer:
high
Explanation:
The energy needed to ionize a neutral atom is known as ionization energy. An atom must have one or more electrons removed from its valence shell in order to get ionized and become a cation. Alternately, you must produce an anion by adding one or more electrons to the valence shell. The energy needed for ionization will be lower the fewer electrons are supplied or withdrawn. As a result, atoms having an incomplete valence shell have a tendency to ionize more quickly and with less energy. However, entire valence shell atoms will require a large amount of ionization energy. As a result, noble gases need significant energy to ionize since they contain a full valence shell, are extremely stable, and do not tend to ionize easily.
10.0 g of nickel is cooled to 2.0 °C and
placed into a sample of warm water.
The final temperature of the water and
nickel was 63.4 °C. How much energy
is absorbed by the nickel?
J
CNi = 0.120 g. C
9Ni = [?] J
Answer:
73.68 J
Explanation:
To find the energy absorbed by nickel, you need to use the following equation:
Q = mcΔT
In this equation,
-----> Q = energy (J)
-----> m = mass (g)
-----> c = specific heat (J/g°C)
-----> ΔT = change in temperature
The change in temperature is found by subtracting the initial temperature from the final temperature. You can plug the given values into the equation and simplify to find the energy absorbed.
m = 10.0 g
c = 0.120 J/g°C
ΔT = 63.4 °C - 2.0 °C = 61.4 °C
Q = mcΔT
Q = (10.0 g)(0.120 J/g°C)(61.4 °C)
Q = 73.68 J
Which of the following is the best definition of a chemical change?
A. All of these
B. The ability of something to undergo a change or reaction.
C. A change that alters the identity, or chemical composition, of a substance at the atomic level.
D. Something that can be observed or measured without changing the identity of the substance.
Chemical changes are changes that alter the identity or the chemical composition of substances at the atomic level.
What are chemical changes?When a substance changes chemically, the identity of the substance changes.
In other words, chemical changes are changes that occur to substances such that the entire chemical properties of the substances change.
These changes happen at the atomic levels of substances. Sometimes, the changes can also be physical as well.
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When a water heater thermostat is set at 140 ° f or higher, a ______ should be installed to cool the water.
Tempering Valve should be installed to cool the water.
A tempering valve is also called an anti-scald valve.
The thermostat controls the temperature inside the tank between 120F to 140F.
A thermostat is just a switch that is actuated by temperature. The thermostat will activates one of the elements in response to a "request for heat" when it detects a water temperature below its predetermined point.
At 140 degrees F temperature water can cause a burn to the skin in five seconds.
The Tempering valve is the mixing chamber, where cold water is mixed with hot water.
It functions as a mixing device, mixing hot and cold water to generate the proper water temperature that is emitted from a certain outlet.
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Describe the difference between radiopaque and radiolucent. Radiopaque refers to a _______________ or light appearance of a structure on a processed radiograph. Radiolucent refers to a _______________ appearance of a structure on a processed radiograph.
Radiopaque refers to a White or light appearance of a structure on a processed radiograph. Radiolucent refers to a Dark appearance of a structure on a processed radiograph.
What makes something radiodense as opposed to radiolucent?Materials that prevent electromagnetic radiation from passing through are referred to as radiodense or radiopaque, whereas materials that permit radiation to pass more readily are referred to as radiolucent. In contrast to radiolucent volumes, which appear significantly darker on radiographs, radiopaque volumes of material seem white.
What exactly does radiodensity mean?It is the relative inability of radio waves and X-rays to flow through a certain substance. Radiodensity (or radiopacity) is opacity to the radio wave and X-ray portion of the electromagnetic spectrum.
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Calculate the concentration of a solution if 15 g of salt is added to 170 g of water.
Considering the definition of percentage by mass, the concentration of a solution if 15 g of salt is added to 170 g of water is 8.108 %.
Percentage by massThe percentage by mass expresses the concentration and indicates the amount of mass of solute present in 100 grams of solution.
In other words, the percentage by mass of a component of the solution is defined as the ratio of the mass of the solute to the mass of the solution, expressed as a percentage.
The percentage by mass is calculated as the mass of the solute divided by the mass of the solution, the result of which is multiplied by 100 to give a percentage. This is:
[tex]percentage by mass=\frac{mass of solute}{mass of solution}x100[/tex]
Concentration of the solutionIn this case, you know:
mass of solute= 15 gmass of water= 170 gmass of solution= mass of solute + mass of water= 15 + 170 g= 185 gReplacing in the definition of percentage by mass:
[tex]percentage by mass=\frac{15 grams}{185 grams}x100[/tex]
Solving:
percent by mass= 8.108 %
Finally, the concentration of a solution if 15 g of salt is added to 170 g of water is 8.108 %.
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How many carbon monoxide molecules are in 0.75 moles of carbon monoxide?
Answer:
four 0.5 times 10 to the 23rd Adams of Neptune
Explanation:
Answer:
0.75 ( 6.02 × 10²³) = 4.515 x 10²³
Explanation:
0.75 ( 6.02 × 10²³) = 4.515 x 10²³
a sodium hydroxide solution is 19 M. What will the strength of the solution formed if 25 ml of this NaOH solutio nis diluted to 5.0 Liters
the strength of the solution formed is 3.8.
What is the strength of the solution?The amount of solute dissolved in grammes per litre of the solution is used to determine the solution's strength. It stands for the solution's potency or concentration. It uses grammes per litre of expression.
Concentration of NaOH = 19 M
Initial volume of NaOH = 25 mL= 0.025 L
Moles of NaOH = 19*0.025
= 0.475 moles
Final volume of NaOH solution = 5 L
Final concentration = 0.475/5
= 0.095 M
so, the strength is 19/5
= 3.8
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