Answer:
- Weight 333.3 grams of iodine.
- Measure 500 mL of water.
- Vigorously mix the resulting solution.
Explanation:
Hello,
In this case, since 500 mL of a 40% (w/v) aqueous solution iodine is required, we can compute the required mass of iodine by defining the given mass-volume percent:
[tex]\% w/v=\frac{m_{iodine}}{m_{solution}} *100%=\frac{m_{iodine}}{m_{water}+m_{iodine}} *100%[/tex]
In such a way, we need to find mass of iodine, which is computed as:
[tex]m_{iodine}=\frac{\%w/v*m_{water}}{100w/v-\%} \\\\m_{iodine}=\frac{40*500}{100-40}\\ \\m_{iodine}=333.3g\\[/tex]
Thereby, the procedure will be:
- Weight 333.3 grams of iodine.
- Measure 500 mL of water.
- Vigorously mix the resulting solution.
Best regards.
HELP! How is the mass number of an atom calculated?
A - total number of electrons
B - total number of protons
C - protons plus neutrons
D - electrons plus neutrons
A strand of messenger RNA coding the synthesis of a protein with 146 amino acids must have a string of___________ bases along its backbone. a. 146 b. 292 c. 438 d. 20 e. 3
Answer:
Since the relationship between amino acid and codon bases would be the values of 3 nitrogenous bases per 1 amino acid.
knowing this relationship what you would do is simply multiply 146 x 3 to find the number of codon bases which would be C. 438.
A strand of messenger RNA coding the synthesis of a protein with 146 amino acids must have a string of 438 bases along its backbone and the correct option is option C.
What is messenger RNA?mRNA or messenger RNA is a single stranded RNA molecule. It is complementary to the DNA and carries genetic information present in the DNA. It is translated to form proteins. The genetic codes (triplet) present on mRNA get translated to amino acids, giving rise to the functional product of a gene.
So mRNA really is a form of nucleic acid, which helps the human genome which is coded in DNA to be read by the cellular machinery. mRNA is actually the translated form of DNA that the machinery can recognize and use to assemble amino acids into proteins.
Each strand has 3 bases, so 146 × 3 = 438 bases
Therefore, A strand of messenger RNA coding the synthesis of a protein with 146 amino acids must have a string of 438 bases along its backbone and the correct option is option C.
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Read the chemical equation. Mg + 2HCl → MgCl2 + H2 How many moles of MgCl2 are produced from 1 mole of HCl? 0.2 0.5 1.0 1.5
Answer:
0.5 mol MgCl₂
Explanation:
Step 1: Write the balanced equation
Mg + 2 HCl → MgCl₂ + H₂
In words, 1 mole of Mg reacts with 2 moles of HCl to form 1 mole of MgCl₂ and 1 mole of H₂.
Step 2: Establish the appropriate molar ratio
The molar ratio of HCl to MgCl₂ is 2:1.
Step 3: Calculate the moles of MgCl₂ produced from 1 mole of HCl
1 mol HCl × (1 mol MgCl₂/2 mol HCl) = 0.5 mol MgCl₂
Answer:
it is 2.0, the above one is wrong
Explanation:
I did the test :
A student mixed 50 ml of 1.0 M HCl and 50 ml of 1.0 M NaOH in a coffee cup calorimeter and calculate the molar enthalpy change of the acid-base neutralization reaction to be –54 kJ/mol. He next tried the same experiment with 100 ml of 1.0 M HCl and 100 ml of 1.0 M NaOH. The calculated molar enthalpy change of reaction for his second trial was:
Answer: The calculated molar enthalpy change of reaction for his second trial was -108 kJ.
Explanation:-
Molarity of a solution is defined as the number of moles of solute dissolved per Liter of the solution.
[tex]\text{no of moles}={\text{Molarity}\times {\text{Volume in L}}[/tex]
Thus [tex]\text{no of moles}of HCl={1.0M}\times {0.05L}=0.05moles[/tex]
Thus [tex]\text{no of moles}of NaOH={1.0M}\times {0.05L}=0.05moles[/tex]
[tex]HCl(aq)+NaOH(aq)\rightarrow NaCl(aq)+H_2O(l)[/tex]
Given for second trial:
[tex]\text{no of moles}of HCl={1.0M}\times {0.1L}=0.1moles[/tex]
[tex]\text{no of moles}of NaOH={1.0M}\times {0.1L}=0.1moles[/tex]
0.05 moles of [tex]HCl[/tex] reacts with 0.05 moles of [tex]NaOH[/tex] to release heat = 54 kJ
0.1 moles of [tex]HCl[/tex] reacts with 0.05 moles of [tex]NaOH[/tex] to release heat =[tex]\frac{54}{0.05}\times 0.1=108kJ[/tex]
Thus calculated molar enthalpy change of reaction for his second trial was -108 kJ.
If the dissolution of borax in water is spontaneous, is the change in enthalpy positive or negative - or are both signs possible?
Answer:
"Both signs are possible" is the correct choice.
Explanation:
The indication including its change in enthalpy depends on the concentration.As when the enthalpy seems to be negative besides purposeful unexpected temperatures lower, as well as successful for necessary response at extremely high temperatures.As such that when both signals could have been the enthalpy change.
If the dissolution of borax in water is spontaneous, so the change in enthalpy should be negative.
What is enthalpy?Enthalpy of the reaction tells about the total amount of energy released or absorbed during any chemical reaction.
And for the spontaneous reaction, value of standard Gibb's free energy change of the reaction should be negative and formula will be represented as:
ΔG = ΔH - TΔS, where
ΔH = change in enthalpy
For the spontaneous reaction, value of enthalpy should be negative so that we get the negative value of ΔG.
Hence change in enthalpy should be negative.
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discuss four factors of learning
Answer:
plz mark as BRAINLIEST plz...
Explanation:
●Intellectual factor: The term refers to the individual mental level. ...
●Learning factors: ...
●Physical factors: ...
●Mental factors: ...
0.25 L of aqueous solution contains 0.025g of HCLO4 (strong acid) what will be the Ph of the solution g
Answer:
The pH of the solution will be 3
Explanation:
The strength of acids is determined by their ability to dissociate into ions in aqueous solution. A strong acid is any compound capable of completely and irreversibly releasing protons or hydrogen ions, H⁺. That is, an acid is said to be strong if it is fully dissociated into hydrogen ions and anions in solution.
Being pH=- log [H⁺] or pH= - log [H₃O⁺] and being a strong acid, all the HClO₃ dissociates:
HClO₄ + H₂O → H₃O⁺ + ClO₄-
So: [HCLO₄]= [H₃O⁺]
The molar concentration is:
[tex]molar concentration=\frac{number of moles of solute}{volume solution}[/tex]
The molar mass of HClO₄ being 100 g / mole, then if 100 grams of the compound are present in 1 mole, 0.025 grams in how many moles are present?
[tex]moles of HClO_{4} =\frac{0.025 grams*1 mole}{100 grams}[/tex]
moles of HClO₄= 0.00025
Then:
[tex][HClO_{4}]=\frac{0.00025 moles}{0.25 L}[/tex]
[tex][HClO_{4}]=0.001 \frac{ moles}{ L}[/tex]
Being [HCLO₄]= [H₃O⁺]:
pH= - log 0.001
pH= 3
The pH of the solution will be 3
A hypothetical atom has four unequally spaced energy levels in which a single electron can be found. Suppose a collection of the atoms are excited to the highest of the four levels. What is the maximum number of unique spectral lines that could be measured as the atoms relax and return to the lowest, ground state
Answer:
[tex]X=6[/tex]
Explanation:
From the question we are told that:
Energy levels [tex]n=4[/tex]
Generally, the equation for spectral lines is mathematically given by
[tex]X=\frac{n(n-1)}{2}[/tex]
[tex]X=\frac{4(4-1)}{2}[/tex]
[tex]X=6[/tex]
If the heat released during condensation goes only to warming the iron block, what is the final temperature (in ∘C) of the iron block? (Assume a constant enthalpy of vaporization for water of 44.0 kJ/mol and a heat capacity for iron of 0.449 J⋅g−1⋅∘C−1.)
Answer:
[tex]91°C[/tex]
Explanation:
CHECK THE COMPLETE QUESTION BELOW;
Suppose that 0.95 g of water condenses on a 75.0 g block of iron that is initially at 22 °c. if the heat released during condensation is used only to warm the iron block, what is the final temperature (in °c) of the iron block? (assume a constant enthalpy of vaporization for water of 44.0 kj/mol.)
Heat capacity which is the amount of heat required to raise the temperature of an object or a substance by one degree
From the question, it was said that that 0.95 g of water condenses on the block thenwe know that Heat evolved during condensation is equal to the heat absorbed by iron block.
Then number of moles =given mass/ molecular mass
Molecular mass of water= 18 g/mol
Given mass= 0.95 g
( 0.95 g/18 g/mol)
= 0.053 moles
Then Heat evolved during condensation = moles of water x Latent heat of vaporization
Q= heat absorbed or released
H=enthalpy of vaporization for water
n= number of moles
Q=nΔH
Q = 0.053 moles x 44.0 kJ/mol
= 2.322 Kj
=2322J
We can now calculate Heat gained by Iron block
Q = mCΔT
m = mass of substance
c = specific heat capacity
=change in temperature
m = 75 g
c = 0.450 J/g/°C
If we substitute into the above formula we have
Q= 75 x 0.450 x ΔT
2322 = 75 x 0.450 x ΔT
ΔT = 68.8°C
Since we know the difference in temperature, we can calculate the final temperature
ΔT = T2 - T1
T1= Initial temperature = 22°C
T2= final temperature
ΔT= change in temperature
T2 = T1+ ΔT
= 68.8 + 22
= 90.8 °C
=91°C
Therefore, final temperature is [tex]91°C[/tex]
The final temperature of the iron block is 91∘C.
Given that;
Heat lost during condensation of the water = Heat gained by iron block
Mass of water(mw) = 0.95 g
Latent heat of vaporization = Latent heat of condensation(L) = 44.0 kJ/mol
Mass of iron(mi) = 75.0 g
Initial temperature of iron(T1) = 22∘C
Final temperature of iron(T2) = ?
Heat capacity of iron(ci) = 0.449 J⋅g−1⋅∘C−1
So;
mwL = mici(T2 - T1)
Substituting values;
(0.95g/18g/mol) × 44.0 × 10^3(J/mol) = 75.0(g) × 0.449 J⋅g−1⋅∘C−1 (T2 - 22∘C)
2322.2 = 33.7T2 - 741.4
2322.2 + 741.4 = 37.4T2
T2 = (2322.2 + 741.4)/ 33.7
T2 =91∘C
Missing parts;
Suppose that 0.95 g of water condenses on a 75.0 g block of iron that is initially at 22 °c. if the heat released during condensation is used only to warm the iron block, what is the final temperature (in °c) of the iron block? (assume a constant enthalpy of vaporization for water of 44.0 kj/mol.)
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arrange the metals sodium,copper, and magnesium in the decreasing order of their reactivity
Answer:
sodium>magenisium>copper
A reaction mechanism has the following proposed elementary steps:Step 1: A → B + CStep 2: A + B → DStep 3: 2 A + D → C + EIf Step 2 is the rate-limiting step, what would the proposed rate law for this mechanism be?
Answer: [tex]Rate=k[A][B][/tex]
Explanation:
Rate law says that rate of a reaction is directly proportional to the concentration of the reactants each raised to a stoichiometric coefficient determined experimentally called as order.
Order of the reaction is defined as the sum of the concentration of terms on which the rate of the reaction actually depends. It is the sum of the exponents of the molar concentration in the rate law expression.
For reactions which takes place in multiple steps are complex reactions and the order is given by the slowest step which is the rate limiting step.
For the given reaction, the rate limiting step is
[tex]A+B\rightarrow D[/tex]
Rate law will be , [tex]Rate=k[A][B][/tex]
what surface phenomenon s
The special properties of surface layers, that is, the thin layers of a substance at the boundary of contiguous bodies, mediums, or phases. These properties result from the excess free energy of the surface layer and from the special features of the layer's structure and composition.
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What would be the name of this compound?
Answer:
2,3 Dimethyl hexane
Explanation:
First, start the count from which side is given the CH3 smallest number
first; the longest carbon chain in this compound is 6
and you don't have any double and triple bonds or functional groups so it is Hexane
you start to count from the right side to give the branch molecules the smallest number ..
CH3 = methyl
and you have 2 methyl in this compound ..
and 2 mean you must write ( Di )
you write the name in this way
2,3 Dimethyl hexane
hope this helps you.
stay safe ...
Which of the following correctly summarizes the
relative composition of the lithosphere with
respect to inorganic and organic material?
A) inorganic >> organic
B) inorganic = organic
C) inorganic << organic
D) There is no organic matter in the lithosphere
Answer:
A
Explanation:
The lithosphere represents the layer of hardened/solid rock that makes up the hard part of the earth, including the brittle upper portion of the mantle and the crust. The lithosphere is broken into pieces that are referred to as plates. The pieces move to and away from each other in a process known as plate tectonics. The movement of plates accounts for the global locations of volcanoes, earthquakes, and mountain ranges.
The lithosphere is made of largely of inorganic materials known as silicates. The weathering of the solid rocks together with the interaction of living organisms gives rise to soil with an appreciable amount of organic materials.
The correct option is, therefore A.
Comparing the 2-bromobutane + methoxide and 2-bromobutane + t-butoxide reactions, choose the statements that BEST describe the data and mechanism. a. the mechanism for this reaction is E2 b. an increase in 1-butene was observed when t-butoxide was used c. an increase in 1-butene was observed when methoxide was used d. the mechanism for this reaction is E1 e. no significant difference was observed
Answer:
an increase in 1-butene was observed when t-butoxide was used
Explanation:
When a base reacts with an alkyl halide, an elimination product is formed. This reaction is an E2 reaction.
Here we are to compare the reaction of two different bases with one substrate; 2-bromobutane. Both reactions occur by the E2 mechanism but follow different transition states due to the size of the base.
The Saytzeff product, 2-butene, is obtained when the methoxide is used while the non Saytzeff product, 1-butene, is obtained when t-butoxide is used.
The Saytzeff rule is reliable in predicting the major products of simple elimination reactions of alkyl halides given the fact that a small/strong bases is used for the elimination reaction. Therefore hydroxide, methoxide and ethoxide bases give similar results for the same alkyl halide substrate. Bulky bases such as tert-butoxide tend to yield a higher percentage of the non Saytzeff product and this is usually attributed to steric hindrance.
Q 13.3: Which of the following is the least stable radical choice? Tertiary radical. B : Allyl radical. C : Secondary radical. D : Methyl radical. E : Primary radical.
Answer:
Methyl radical
Explanation:
A radical is any specie that contains an odd number of electrons. We must note that the greater the number of alkyl groups which are attached to a carbon atom that bears the odd electrons, the more the degree of delocalization of the odd electrons and consequently the more stable we expect the free radical to be.
Hence the order of free radical stability is; Methyl < Primary < Secondary < Tertiary. Hence, we can easily see that the methyl radical is the least stable free radical.
Answer: Methyl radical
Explanation:
Draw the structure of beeswax.beeswax is made from the esterfication of a saturated 16-carbon fatty acid and a 30 carbon straight chain primary alcohol.
Answer:
Triacontyl palmitate
Explanation:
In this case, we have a reaction between an acid and an alcohol. When we put together these kind of compounds an ester is produced. This reaction is called "esterification".
In our case, the alcohol is a structure with 30 carbon in which the "OH" group is bonded on carbon 1. The name of this compound is "n-triacontanol". The acid is a structure in which we have 16 carbon in which the "COOH" group is placed on carbon 1. The name of this compound is "palmitic acid". The ester produced by the acid and the alcohol is "Triacontyl palmitate".
See figure 1.
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An outdoor gear company develops a new type of fabric that works with electricity to warm the body without interfering with motion like heavy jackets do. Research biologists, studying life in extremely cold conditions on the polar ice caps, begin wearing the new fabric because it helps them work more comfortably, and they find it increases their productivity.
What best describes how the processes of scientific investigation and technological design are involved in this situation?
The clothing company conducted a scientific investigation to communicate results to researchers, who then used the knowledge in a technological design.
The clothing company conducted a scientific investigation to produce a product that researchers could then test while designing new technology.
The clothing company used technological design to create a product that helped aid researchers conducting a scientific investigation.
The clothing company designed a new technology that provided information researchers needed in order to continue with their scientific investigation.
Answer:
C: The clothing company used technological design to create a product that helped aid researchers conducting a scientific investigation.
Explanation:
I just did the assignment on EDGE2020 and it's 200% correct!
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What is the concentration of MgSO4 in a solution prepared by dissolving 30g MgSO4 in 500ml distilled water. Express concentration in
(i)ppm
(ii) %w/v
(iii) %w/w
Assume the solution density is 1.15g/ml.
Answer:
Concentration of MgSO4 = 0.0521 × 10⁶ ppmConcentration of MgSO4 = 6% w/vConcentration of MgSO4 = 5.21% w/wExplanation:
Given:
Mass of solute = 30 gram
Volume of water = 500 ml
Density = 1.15g/ml
Find:
(i)ppm
(ii) %w/v
(iii) %w/w
Computation:
Water in gram = 500 ml × 1.15 g/ml
Water in gram = 575 gram
In ppm
Concentration of MgSO4 = [30 / 575] × 10⁶
Concentration of MgSO4 = 0.0521 × 10⁶ ppm
in % w/v
Concentration of MgSO4 = [30 / 500] × 100
Concentration of MgSO4 = 6% w/v
in % w/w
Concentration of MgSO4 = [30 / 575] × 100
Concentration of MgSO4 = 5.21% w/w
The complex ion Fe(CN)63- is paramagnetic with one unpaired electron. The complex ion Fe(SCN)63- has five unpaired electrons. Where does SCN- lie in the spectrochemical series with respect to CN-?
Answer:
SCN- is a weak field ligand while CN- is a strong field ligand
Explanation:
The spectrochemical series is an arrangement of ligands according to their magnitude of crystal field splitting. Ligands that cause only a small degree of crystal field splitting are called weak field ligands while ligands that cause large crystal field splitting are called strong field ligands.
Strong field ligands often lead to the formation of low spin complexes with the least number of unpaired electrons while high spin complexes are formed by weak field ligands.
CN- is a strong field ligand as it lies towards the right hand side of the spectrochemical series.
SCN- is a weak field ligand hence it forms a high spin complex having the maximum number of unpaired electrons for Fe^3+, hence the answer.
SCN⁻ lies in the lower (weak field) region of the spectrochemical series while CN⁻ lies in the higher (stronger field) region.
CN⁻ is a strong field ligand with a large splitting constant, and it is high up in the spectrochemical series.
Conversely, SCN⁻ is a weak field ligand with a low splitting constant, and it is lower in the spectrochemical series.
Hence, SCN⁻ lies in the lower (weak field) region of the spectrochemical series while CN⁻ lies in the higher (stronger field) region.
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Compound has a molar mass of and the following composition: elementmass % carbon47.09% hydrogen6.59% chlorine46.33% Write the molecular formula of .
The given question is incomplete. The complete question is:
Compound X has a molar mass of 153.05 g/mol and the following composition:
element mass %
carbon 47.09%
hydrogen 6.59%
chlorine 46.33%
Write the molecular formula of X.
Answer: The molecular formula of X is [tex]C_6H_{10}Cl_2[/tex]
Explanation:
If percentage are given then we are taking total mass is 100 grams.
So, the mass of each element is equal to the percentage given.
Mass of C= 47.09 g
Mass of H = 6.59 g
Mass of Cl = 46.33 g
Step 1 : convert given masses into moles.
Moles of C =[tex]\frac{\text{ given mass of C}}{\text{ molar mass of C}}= \frac{47.09g}{12g/mole}=3.92moles[/tex]
Moles of H =[tex]\frac{\text{ given mass of H}}{\text{ molar mass of H}}= \frac{6.59g}{1g/mole}=6.59moles[/tex]
Moles of Cl =[tex]\frac{\text{ given mass of Cl}}{\text{ molar mass of Cl}}= \frac{46.33g}{35.5g/mole}=1.30moles[/tex]
Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.
For C = [tex]\frac{3.92}{1.30}=3[/tex]
For H = [tex]\frac{6.59}{1.30}=5[/tex]
For Cl =[tex]\frac{1.30}{1.30}=1[/tex]
The ratio of C : H: Cl= 3: 5 :1
Hence the empirical formula is [tex]C_3H_5Cl[/tex]
The empirical weight of [tex]C_3H_5Cl[/tex] = 3(12)+5(1)+1(35.5)= 76.5g.
The molecular weight = 153.05 g/mole
Now we have to calculate the molecular formula.
[tex]n=\frac{\text{Molecular weight }}{\text{Equivalent weight}}=\frac{153.05}{76.5}=2[/tex]
The molecular formula will be=[tex]2\times C_3H_5Cl=C_6H_{10}Cl_2[/tex]
What is the volume of a 1100 g block of gold?
Answer:
The metal block had a mass of 1.50kg
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Answer:according to this picture
Explanation:
The absorption spectrum of argon has a line at 515 nm. What is the energy of
this line? (The speed of light in a vacuum is 3.00 x 108 m/s, and Planck's
constant is 6.626 x 10-34 Jos.)
O A. 2.59 x 1027j
O B. 3.86 x 10-28 J
O C. 3.86 x 10-19 J
O D. 2.59 x 1018 J
Answer:
OPTION C is correct
3.86 x 10-19 J
Explanation:
Energy of the line can be calculated using below formula
E= h ν.................(1)
Where E= energy
h= plank constant= 6.626 10-34 J s
c=speed of light=3 x 108 m/s
But we know that Velocity V= = c / λ
Then substitute into equation (1) we have
E = h c / λ.............(2)
We can calculate our( hc ) in nm for unit consistency
h c =( 6.626 ×10^-34)x(3×108)
h c = (1.986 x 10-16 )
hc = 1.986 x 10-16 J nm then since our (hc) and λ are in the same unit , were good to go then substitute into equation(2)
E = h c / λ = (1.986 x 10-16) / 515
E = 3.86 x 10-19 J
Therefore, the Energy is 3.86 x 10-19 J
Increasing which factor will cause the gravitational force between two objects to decrease?
weights of the objects
distance between the objects
acceleration of the objects
masses of the objects
Answer:
B
Explanation:
Increasing distance between the objects factor will cause the gravitational force between two objects to decrease. Therefore, option B is correct.
What causes gravitational force to decrease?The gravitational force grows in proportion to the size of the masses . The gravitational force weakens rapidly as the distance between masses grows. Unless at least one of the objects has a lot of mass, detecting gravitational force is extremely difficult.
Gravity is affected by object size and distance between objects. Mass is a unit of measurement for the amount of matter in an object.
The force of gravity is proportional to the masses of the two objects and inversely proportional to the square of the distance between them. This means that the force of gravity increases with mass but decreases as the distance between objects increases.
Thus, option B is correct.
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Which gas will have the most collisions between its particles?
Answer:
The gas is Methane at 340K
You have a saturated solution of BaSO4, a slightly soluble ionic compound. What happens if you add Ba(OH)2, NaNO3, and CuSO4 to this solution
Answer:
- Addition of Ba(OH)2: favors the formation of a precipitate.
- Undergo a chemical reaction forming soluble species.
- Addition of CuSO4 : favors the formation of a precipitate.
Explanation:
Hello,
In this case, since the dissociation reaction of barium sulfate is:
[tex]BaSO_4(s)\rightleftharpoons Ba^{2+}(aq)+SO_4^{2-}(aq)[/tex]
We must analyze the effect of the common ion:
- By adding barium hydroxide, more barium ions will be added to the equilibrium system so the formation of solid barium sulfate will be favored (reaction shifts leftwards towards reactants).
- By adding sodium nitrate, the following reaction will undergo:
[tex]BaSO_4(s)+NaNO_3(aq)\rightarrow Ba(NO_3)_2(aq)+Na_2SO_4(aq)[/tex]
So the precipitate will turn into other soluble species.
- By adding copper (II) sulfate, more sulfate ions will be added to the equilibrium system so the formation of solid barium sulfate will be favored (reaction shifts leftwards towards reactants).
All of this is supported by the Le Chatelier's principle.
Best regards.
4. A 0.100 M solution of NaOH is used to titrate an HCl solution of unknown concentration. To neutralize the solution, an average volume of
the titrant was 38.2 mL. The starting volume of the HCI solution was 20 ml. What's the concentration of the HCI?
O A.0.284 M
B. 3.34 M
C. 0.191 M
D. 0.788 M
Answer:
C. 0.191 M
Explanation:
Our goal for this question, is to calculate the concentration of the HCl solution. For this, in the experiment, a solution of NaOH was used to find the moles of HCl. Therefore, our first step is to know the reaction between HCl and NaOH:
[tex]HCl~+~NaOH~->~NaCl~+~H_2O[/tex]
The "titrant" in this case is the NaOH solution. If we know the concentration of NaOH (0.100M) and the volume of NaOH (38.2 mL=0.0382 L), we can calculate the moles using the molarity equation:
[tex]M=\frac{mol}{L}[/tex]
[tex]0.100~M=\frac{mol}{0.0382~L}[/tex]
[tex]mol=0.100~M*0.0382~L=0.0382~mol~of~NaOH[/tex]
Now, in the reaction, we have a 1:1 molar ratio between HCl and NaOH (1 mol of HCl is consumed for each mole of NaOH added). Therefore we will have the same amount of moles of HCl in the solution:
[tex]0.0382~mol~of~NaOH\frac{1~mol~HCl}{1~mol~NaOH}=0.0382~mol~HCl[/tex]
If we want to calculate the molarity of the HCl solution we have to divide by the litters of HCl used in the experiment (20 mL= 0.02 L):
[tex]\frac{0.0382~mol~HCl}{0.02~L}~=~0.191~M[/tex]
The concentration of the HCl solution is 0.191 M
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The following is what kind of reaction?
2 CH4 +4 02 → 2 CO2 + 4H2O
Answer:
It is a combustion reaction.
Chlorine can be prepared in the laboratory by the reaction of manganese dioxide with hydrochloric acid, HCl(aq), as
described by the chemical equation
MnO,(s) + 4 HCl(aq)
MnCl(aq) + 2 H2O(l) + Cl (8)
How much MnO(s) should be added to excess HCl(aq) to obtain 175 mL C12(g) at 25 °C and 715 Torr?
mass of MnO2
Answer:
Explanation:
MnO₂(s) + 4 HCl(aq) = MnCl₂(aq) + 2 H₂O(l) + Cl₂
87 g 22.4 x 10³ mL
volume of given chlorine gas at NTP or at 760 Torr and 273 K
= 175 x ( 273 + 25 ) x 715 / (273 x 760 )
= 179.71 mL
22.4 x 10³ mL of chlorine requires 87 g of MnO₂
179.4 mL of chlorine will require 87 x 179.4 / 22.4 x 10³ g
= 696.77 x 10⁻³ g
= 696.77 mg .
Please help fast
All four referenced Greek thinkers: Democritus, Aristotle, Archimedes, and Anaxagoras, observed Nature and argued for his theory of
the composition of matter and natural laws. Only one of them tested his hypothesis and proposed a natural laws based on reproducible
observations, controlled experiments, and mathematical reasoning. All others used logic and thought experiments, as philosophers do,
to support their theories. Who is the experimental scientist in this group?
O Democritus
O Aristotle
O Archimedes
O Anaxagoras
Answer:
Anaxagoras was perhaps the first literate person to attempt to explain physical phenomena rationally, basing his ideas upon careful observations and simple experiments. This is fundamental to modern science and is the sine qua non of environmental study.