Answer:
b d my good mannnnnnnnnnnn
A balloon has a volume of 1785 mL at 25°C, if the volume of balloon changes to 1.25 L, what is the new temperature in degree Celcius atconstant pressure and amount?
We work here with Charles' Law. The equation used here is:
V1/T1 = V2/T2 (1)
(pressure and amount constant)
V is for volume and T for temperature
V1 = 1785 mL
1 L = 1000 mL ==> V1 = 1.785 L
T1 = 25 °C = 25 °C + 273 = 298 K
V2 = 1.25 L
T2 = unknown
From (1) we clear T2:
T2 = V2 x T1/V1 = 1.25 L x 298 K/1.785 L = 209 K approx.
T2 = 209 K - 273 = -64 °C
Answer: T2 = -64 °C
Select the correct answer.
Consider an atom that has an electron in an excited state. The electron falls to a lower energy level. What effect does that have on the electron?
The electron releases energy in the form of light.
Hope this helps!
What is the electronic configuration of argon
Electronic configuration: this shows us the distribution of electrons in an atom. The chart below helps us find the electron configuration.
How many protons does argon have?
Argon has 18 protons.
The electronc configuration of argon is 1s2 2s2 2p6 3s2 3p6
stomach acid has a pH of 1 and tomatoes have a pH of 4. How many times stronger than tomatoes is stomach acid?
We must take into account the definition of pH, and this represents the concentration of H+ ions([H+]). It can be defined with the following equation:
[tex]pH=-\log \lbrack H^+\rbrack[/tex]To determine how many times the acid is stronger than the tomato, we must calculate the concentration of H+ ions for each pH value, to do so we clear [H+] from the previous equation:
[tex]\lbrack H^+\rbrack=10^{-pH}[/tex]Now we substitute each pH value into the equation:
[tex]\begin{gathered} \lbrack H^+\rbrack_{StomachAcid}=10^{-1} \\ \lbrack H^+\rbrack_{\text{Tomatoes}}=10^{-4} \end{gathered}[/tex]Therefore we will have to:
[tex]\frac{\lbrack H^+\rbrack_{StomachAcid}}{\lbrack H^+\rbrack_{\text{Tomatoes}}}=\frac{10^{-1}}{10^{-4}}=\frac{1}{10^{-3}}=10^3=1000[/tex]Therefore, stomach acid will be 1000 times stronger than the tomatoes.
Balance the equation
type your answer...
Previous
H₂+ type your answer...
O2 type your answer...
H₂O
The balanced equation
2H2 +O2 =====> 2H2O
What is balanced equation ?
An equation for a chemical reaction is said to be balanced if both the reactants and the products have the same number of atoms and total charge for each component of the reaction. In other words, both sides of the reaction have an equal balance of mass and charge.
The balanced equation
2H2 +O2 =====> 2H2O
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Select all possible problems associated with using nuclear fusion reactions as an energy source. Nuclear fusion occurs at temperatures of millions of degrees Celsius.Research reactors require more energy to maintain these temperatures than the energy the reaction produces.Nuclear fusion occurs at negative degree Celsius temperatures to create unstable reactions to use as an energy sourceIt is difficult to contain the fusion reaction under such extreme conditions.
Answer:
[tex]A,B\text{ and D}[/tex]Explanation:
Here, we want to select the possible problems with nuclear fusion
Nuclear fusion refers to a nuclear reaction wherein two or more daughter nuclei combines to give a larger nucleus
Let us look at the options one after the other to check which of them is correct
a) This is correct
The temperature accompanying nuclear reactions is millions of degrees celsius which are very high
b) This is Correct
This is the major reason why there are currently no nuclear reactors that use fusion to provide energy
c) This is wrong
They occur at very high temperatures. The nuclei need very high energy to send them into kinetic motion
d) This is correct
It is quite difficult to contain a fusion reaction due to the conditions surrounding it and that is one of the reasons why there are no commercial nuclear reactors that use fusion as an energy source
What is the final concentration when 288mL of water is added to 239mL of a 0.274M solution?
Answer:
0.124 M.
Explanation:
What is given?
Volume 1 (V1) = 239 mL,
Concentration 1 (C1) = 0.274 M,
Volume 2 (V2) = 239 mL + 288 mL = 527 mL.
What do we need? Concentration 2 (C2).
Step-by-step solution:
To solve this problem, we have to use the following formula:
[tex]C_1V_1=C_2V_2.[/tex]Where the initial concentration (C) and volume (V) are represented with subindex 1, and the final concentration and volume are represented with subindex 2.
The problem is telling us that we are adding 288 mL of water to 239 mL, so the final volume is the sum of these two volumes, i.e., 527 mL.
As we want to find the final concentration, C2, we just have to solve for this unknown value and replace the values that we have, like this:
[tex]\begin{gathered} C_2=\frac{C_1V_1}{V_2}, \\ \\ C_2=\frac{0.274\text{ M}\cdot239\text{ mL}}{527\text{ mL}}, \\ \\ C_2=0.124\text{ M.} \end{gathered}[/tex]The answer would be that the final concentration of the solution is 0.124 M.
In the reaction of 2Mg + O2 →2MgO
How many moles of O2 are required to react with 14 moles of Mg?
Answer:
Explanation:The given reaction is
It is an example of an oxidation reaction because in the above reaction, is getting oxidized to form .
Also, it is a type of combination reaction because magnesium reacts with oxygen to form a single product i.e. Magnesium oxide.
A 45 mL sample of calcium chloride stock solution produces a 0.182 M diluted solution by adding 50. mL of water. What is the molarity of the stock solution?
A solution of Calcium Chloride was made, we are asked to find the concentration of the initial solution.
We will apply the following equation to find it:
[tex]C_1V_1=C_2V_2[/tex]Where,
C1 is the initial concentration we have to find
V1 is the initial volume, 45mL
C2 is the final concentration, 0.182M
V2 is the final volume, 50. mL
We clear C1 and replace the known data;
[tex]C_1=\frac{C_2V_2}{V_1}[/tex][tex]\begin{gathered} C_1=\frac{0.182M\times50.mL}{45mL} \\ C_1=0.202M \end{gathered}[/tex]The molarity of the stock solution is 0.202M
Answer: 0.202M
Assuming that each double-displacement reaction occurs, predict the products and write each balanced chemical equation.
a.
Sn(OH)2 + FeBry -*?
b. CsNO3 + KCI -* ?
The products of the double displacement reactions are given in the equations of the reaction below:
a. 3 Sn(OH)₂ (aq) + 2 FeBr₃ (aq) ---> 3 SnBr₂ (aq) + 2 Fe(OH)₃ (s)
Iron (iii) hydroxide is obtained as a precipitate
b. CsNO₃ (aq) + KCI (aq) ---> CsCl (aq) + KNO₃ (aq)
No double displacement reaction occurs as both products are soluble.
What are double displacement reactions?Double displacement reactions are reactions in which there is an exchange of radicals by two compounds when solutions of the compounds are added together.
In a double displacement reaction, an insoluble precipitate is obtained since one of the products of the double displacement reaction is insoluble in aqueous solutions.
The products of the double displacement reactions are given in the equations of the reaction below:
a. Reaction between Sn(OH)₂ and FeBr₃
3 Sn(OH)₂ (aq) + 2 FeBr₃ (aq) ---> 3 SnBr₂ (aq) + 2 Fe(OH)₃ (s)
Iron (iii) hydroxide is obtained as a precipitate
b. Reaction between CsNO₃ and KCI
CsNO₃ (aq) + KCI (aq) ---> CsCl (aq) + KNO₃ (aq)
No double displacement reaction occurs as both products are soluble.
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After centrifugation of the sample, the student was not careful and some of the solid was transferred to the Erlenmeyer flask along with the liquid (supernatant). How is this mistake expected to affect the mass of the limiting reactant in the unknown mixture used?
The fact that some of the solid was transferred would decrease the mass of the limiting reactant.
What is the limiting reactant?We know that in a chemical reaction, there are at least two substances that are combined in order to give the product of the reaction. We also know that the product that we obtain must be in accordance to the stoichiometry of the reaction.
It is common to see that one of the reactants would be present in a very large amount while the other reactant would be present only in quite a small amount. The reactant that is present in a small amount is said to be the limiting reactant while the one that is present in the large amount is said to be the reactant that is in excess.
Having said this, we know that the mass of the limiting reactant can be obtained from the mass of the solid that is obtained after the reaction.
If we do not take out all of the solid from the centrifuge, the mass would not be accurately weighed and the mass of the limiting reactant would not be accurately determined.
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8.In the equation 2 NH3 + H2O + CO2 ---> (NH4)2CO3, which of the following is a product?Select one:a. CO2 b. H2O c. NH3 d. (NH4)2CO3
According to the explanation given in a previous session, the compounds that comes after the arrow are classified as product, and the compounds that comes before are classified as reactant, therefore in this reaction, (NH4)2CO3 is the product of the reaction, letter D
The______of photosynthesis are the____of cellular respirationmeaning their equation are the ame but_____of each other.
Answer:
reactants /products, products / reactants, opposite / inverse
I can't exactly tell how many underscores there are.
Explanation:
This is biology, but it does contain chemistry.
How many grams of carbon monoxide gas would be contained in 710 mL at 119 kPa and 37 C
Answer
0.9166 g CO
Procedure
Considering the conditions and parameters given ideal gas law will be assumed.
[tex]PV=nRT[/tex]The gas constant is 8.3144 L⋅kPa⋅ K⁻¹⋅mol⁻¹
Converting the current data to the required units
710 mL = 0.710 L
37 °C = 310.15 °K
Solving for moles and substituting the variables with the available data
[tex]n=\frac{PV}{RT}=\frac{119\text{ }kPa(0.710)L}{8.3144\text{ L. kPa\cdot}\degree\text{K^^^^207b^^b9\cdot mol^^^^207b^^b9 \lparen310.15\rparen }\degree K}=0.0327\text{ }moles\text{ CO}[/tex]Transforming from moles to grams using the molecular weight
[tex]0.0327\text{ }moles\text{ }CO\frac{28.01\text{ }g}{1\text{ }mole}=0.9166\text{ }g\text{ }CO[/tex]How many kilojoules are required to melt 15g of ice at 0 degrees celsius and raise the temperature of the liquid that forms to 85 degrees celsius.
The amount of heat, in kilojoules, that is required to melt 15 g of ice at 0 degrees Celsius and raise the temperature of the liquid to 85 degrees Celsius is 10.3178 kJ.
Heat changeThe process involves melting of ice at 0 degrees Celsius and then heating the resulting water to a temperature of 85 degrees Celsius.
Solid water is first converted to liquid water without a change in temperature.Liquid water is heated without a change of state to 85 degrees Celsius.Now, let's calculate the heat change of the process:
Heat change (ΔH) = n x heat of fusion) + mcΔt
Where n = number of moles
m = mass = 15 g
c = specific heat capacity of water = 4.81 J/g[tex]^oC[/tex]
heat of fusion = 6010 J/mole
In this case, n = mass/molar mass
= 15/18
= 0.83 moles
ΔH = (0.83 x 6010) + 15 x 4.81 x (85 - 0)
= 10317.8 Joules
But 1000 Joules = 1 kilojoules
Thus, 10317.8 joules = 10.3178 kJ
The kilojoule of heat required to melt the ice and raise the temperature of the resulting water to 85 degrees Celsius is 10.3178 kJ.
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A gas mixture contains 1.26 g N2 and 0.76 g O2 in a 1.51 L container at 11 C. Calculate the partial pressure of N2?
When we have a mixture of gases, the pressure exerted by each depends on the number of moles present in the mixture, this contribution is called partial pressure. The sum of the partial pressures will be equal to the total pressure, this is called Dalton's law.
Partial pressure can be described by the following equation:
[tex]P_i=X_iP_T[/tex]Where,
Pi is the partial pressure
Xi is the molar fraction
Pt is the total pressure
The molar fraction is calculated by the following equation:
[tex]X_i=\frac{n_i}{n_T}[/tex]Where,
ni is the number of moles of the substance
nT is the total number of moles.
So, we have to find first the number of moles of each gas. We are given the grams of gases, to get the equivalent moles we must divide the mass by the molar mass.
Molar Mass N2=28.0134g/mol
Molar Mass O2=31.9988g/mol
[tex]\begin{gathered} molN_2=1.26g\times\frac{1molN_2}{28.0134gN_2}=0.045molN_2 \\ molO_2=0.76gO_2\times\frac{1molO_2}{31.9988gO_2}=0.024molO_2 \end{gathered}[/tex]Now, the partial pressure of N2 will be:
[tex]P_{N2}=\frac{0.045molN_2}{0.045molN_2+0.024molO_2}\times P_T[/tex][tex]P_{N2}=\frac{0.045molN_2}{0.069mol}\times P_T[/tex][tex]P_{N2}=0.652\times P_T[/tex]If we assume that the gas behavior is like an ideal gas, we can find the total pressure with the following equation:
[tex]\begin{gathered} PV=nRT \\ P_T=\frac{nRT}{V_T} \end{gathered}[/tex]Where,
n is the total number of moles, 0.069mol
R is a constant, 0.08206atm.L/mol.K
V is the volume of the gas, 1.51L
T is the temperature of the gas, K.284.15K
We replace the known data:
[tex]P_T=\frac{0.069mol\times0.08206\frac{atm.L}{mol.K}\times284.15K}{1.51L}=1.06atm[/tex]Now, the partial pressure of nitrogen will be:
[tex]P_{N2}=0.652*1.06atm=0.69atm[/tex]Answer: The partial pressure of N2 is 0.69atm
What is the answer for this? I know how to solve it but want to make sure it is correct? (Number 9)
The IUPAC name of the structure (9) is 4-ethyl-2,3-dimethyl-heptane.
What are the steps of IUPAC nomenclature?The first step is to select the longest, most substituted carbon chain containing a functional group is chosen. Then the identification of the primary suffix indicates the degree of saturation such as 'ane' or 'ene.
Then the identification of the secondary suffix indicates the functional group present in the molecule which depends on the number of occurrences of the same functional group such as di. tri tetra etc. Carbon atoms in the carbon chain are numbered from the reactive end of the molecule where the functional group is present.
In the given structure the longest carbon chain of seven carbon atoms. The methyl groups are present at the second and third position and the ethyl group is present at the fourth position. All the bonds in the structure are single bonds so the suffix is 'ane'. Therefore, the IUPAC name is 4-ethyl-2,3-dimethyl-heptane.
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Classify the following compounds as alkane, alkene, alkyne based on the given structure
We have the next compounds
And we must classify them as alkane, alkene, alkyne.
We need to know that
- Alkane: They are the simplest hydrocarbons, containing only carbon and hydrogen held together by single bonds.
- Alkene: Alkenes are hydrocarbons that contain a double bond.
- Alkyne: Alkynes are hydrocarbons that contain a triple bond.
1. We can see that the structure has a double bond. So, it is an Alkene.
2. We can see that the structure has a triple bond. So, it is an Alkyne.
3. We can see that the structure has a double bond. So, it is an Alkene.
4. We can see that the structure has a triple bond. So, it is an Alkyne.
ANSWER:
1. Alkene
2. Alkyne
3. Alkene
4. Alkyne
Using the balanced equation:3 Ag2S + 2 Al -> Al2S3 + 6 Ag0.88 moles of Ag2S = ? grams Ag
Answer: 189.5g of Ag would be produced from 0.88 moles of Ag2S
Explanation:
The question requires us the amount of Ag, in grams, that would be produced from 0.88 moles of Ag2S, according to the following equation:
[tex]3Ag_2S+2Al\rightarrow Al_2S_3+6Ag[/tex]To solve this problem, which is a mol to mass stoichiometry problem, we'll need to follow the steps:
moles of Ag2S → moles of Ag → mass of Ag
To do that, we'll need to use the molar mass of Ag (107.87 g/mol) and the mole ratio between Ag2S and Ag, as given by the balanced chemical equation (6 moles of Ag are produced from 3 moles of Ag2S).
We can calculate the number of moles of Ag that would be produced from 0.88 moles of Ag2S as:
3 mol Ag2S -------------------------- 6 mol Ag
0.88 mol Ag2S --------------------- x
Solving for x, we'll have:
[tex]x=0.88mol\text{ Ag}_2S\times\frac{6mol\text{ Ag}}{3mol\text{ Ag}_2S}=1.76mol\text{ Ag}[/tex]Therefore, 1.76 moles of Ag would be produced from 0.88 moles of Ag2S.
Next, we need to convert the number of moles of Ag calculated to its correspondent mass. Knowing that the molar mass of Ag is 107.87 g/mol, we can calculate:
[tex]\begin{gathered} number\text{ of moles = }\frac{mass\text{ \lparen g\rparen}}{molar\text{ mass \lparen g/mol\rparen}}\rightarrow mass\text{ = number of moles}\times molar\text{ mass} \\ \\ mass\text{ = 1.76mol}\times107.87g/mol=189.8g \end{gathered}[/tex]Therefore, 189.5g of Ag would be produced from 0.88 moles of Ag2S.
What is the relationship between n, ℓ, and the total number of nodes?
The number of planar nodes = ℓ.
The number of spherical nodes = n - ℓ - 1.
The relationship between n, ℓ, and the total number of nodes is given by the expression; Number of spherical nodes = n - ℓ - 1.
What is the number of nodes?The number of nodes has to do with the points on the orbital where there is a zero electron density. It is the points along the orbital where there re no electrons. Recall that the orbitals are the regions in space where there is a high probability of finding an electron.
There are various orbitals and the number of nodes of each of the orbitals does vary. The s orbital has no nodes while the p orbital is known to have one node.
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In one demonstration of this reaction, 39.00 mL of H2 are collected over water at 25°C. Atmospheric pressure is 749.0 mmHg. How many grams of H2 are collected?
Taking into account the ideal gas law, a mass of 0.00314 grams of H₂ is collected.
Definition of ideal gas lawAn ideal gas is a theoretical gas that is considered to be composed of randomly moving point particles that do not interact with each other. Gases in general are ideal when they are at high temperatures and low pressures.
The pressure, P, the temperature, T, and the volume, V, of an ideal gas, are related by a simple formula called the ideal gas law:
P×V = n×R×T
where:
P is the gas pressure.V is the volume that the gas occupies.T is its temperature.R is the ideal gas constant. The universal constant of ideal gases R has the same value for all gaseous substances. The numerical value of R will depend on the units in which the other properties are worked.n is the number of moles of the gas. Mass of H₂In this case, you know:
P= 749 mmHg= 0.985526 atm (being 760 mmHg= 1 atm)V= 39 mL= 0.039 L (being 1000 mL= 1 L)n= ?R= 0.082 (atm×L)÷(mol×K)T= 25 C= 298 K (being 0 C= 273 K)Replacing in the ideal gas law:
0.985526 atm× 0.039 L = n× 0.082 (atm×L)÷(mol×K)× 298 K
Solving:
[0.985526 atm× 0.039 L]÷ [0.082 (atm×L)÷(mol×K)× 298 K]= n
0.00157 moles= n
Considering that the molar mass of H₂ is 2 g/mole, the mass can be calculated as:
mass= number of moles× molar mass
mass= 0.00157 moles× 2 g/mole
mass= 0.00314 grams
Finally, you collected a mass of 0.00314 grams.
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A 4.50 L sample of neon at 11.08 atm is added to a 12.0 L cylinder that contains argon. If the pressure in the cylinder is 7.15 atm after the neon is added, what was the original pressure (in atm) of argon in the cylinder?
The original pressure of argon in the cylinder is 5.68 atm.
What is the original pressure of the argon?
The original pressure of argon in the cylinder is calculated as follows.
Apply the concept of molar ratio or molar proportion to determine the original pressure of argon in the cylinder.
Pr = [(Pn x Vn) + (Pa x Va) ] / (Vn + Va)
where;
Pr is the resultant pressure of the mixture of gases = 7.15 atmPn is the original pressure of neon = 11.08 atmPa is the original pressure of argonVn is the volume of neon = 4.5 LVa is the volume of argon = 12 L7.15 = [(11.08 x 4.5) + (12 x Pa)] / (4.5 + 12)
7.15(4.5 + 12) = 49.86 + 12Pa
117.98 = 49.86 + 12Pa
68.12 = 12Pa
Pa = 68.12/12
Pa = 5.68 atm
Thus, the original pressure of argon in the cylinder is determined by applying concept of molar ratio.
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Consider the following reaction in the forward direction. Identify the base:
CH₃O⁻ + H₂O ⇌ CH₃OH + OH⁻
If we consider the reaction CH₃O⁻ + H₂O ⇌ CH₃OH + OH⁻ in the forward direction, the base in the reaction is CH₃O⁻
A compound can be acidic, basic or neutral in nature. Basicity of the compound is determined when it either releases hydroxide ions, donates electrons or else accepts the protons from a compound.
In the reaction CH₃O⁻ + H₂O ⇌ CH₃OH + OH⁻:
CH₃O⁻ accepts proton or [H+] ion to become CH₃OH. Thus, CH₃O⁻ is the base in the reaction
H₂O donate [H+] ion or proton, therefore H2O change into OH-. Thus, H₂O is an acid in the reaction.
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What is the name of the product formed by the reaction of propylide ion and 2-chloropropane?
30.Vegetable soup is classified as which of the following?Select one:a. An atom.b. A compound.c. An element.d. A mixture.
A mixture in Chemistry is defined as a material made up of two or more different chemical substances, and it will not present a homogeneous solution, but instead a heterogeneous appearance, just like a vegetable soup, which is a mixture of many substances, answer letter D
4. You have 500 grams of MgF2. If a 3 M solution is desired, how many Liters must be present?
They give us the grams of solute and the molarity of the solution. To find the liters we must take into account the definition of molarity. Molarity is defined as:
[tex]Molarity=\frac{MolesSolute}{Lsolution}[/tex]The definition of molarity asks us for the moles of solute, so we must pass the grams that give us to moles. For them, we divide the 500 grams by the molar mass of MgF2. The molar mass of MgF2 is 62.3018g/mol.
The moles of MgF2 will be:
[tex]\begin{gathered} molMgF_2=GivengMgF_2\times\frac{1molMgF_2}{MolarMass,gMgF_2} \\ molMgF_2=500gMgF_2\times\frac{1molMgF_2}{62.3018gMgF_2}=8.03molMgF_2 \end{gathered}[/tex]Now, we find the liters of solution:
[tex]\begin{gathered} Lsolution=\frac{MolesSolute}{Molarity} \\ Lsolution=\frac{8.03mol}{3M}=\frac{8.03mol}{3mol/L} \\ Lsolution=3L \end{gathered}[/tex]Answer: It must be present 3L of solution
How can the bulk properties of a substance (macroscopic) such as electrical conductivity be caused by the microscopic such as electrical forces in the atoms?
The bulk properties of a substance (macroscopic) such as electrical conductivity can be caused by the microscopic such as electrical forces in the atoms through the movement of free electrons.
What is Conductivity?This is referred to as the measure or the degree in which a substance conducts electricity and how the electric current moves within a substance.
The electrical conductivity which is macroscopic can be caused by the microscopic such as electrical forces as a result of the electrons moving in the body. The movement of the electron is usually from the negative to the positive terminal of the body.
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A 25.0 mL aliquot was taken from a 500.0 mL sample of tonic water containing an unknown amount of quinine and diluted to a volume of 200.0 mL. At 347.5 nm, the fluorescence intensity of the diluted sample was measured as 73.7 on an arbitrary scale. Under similar conditions, a 25.0 ppm standard quinine solution had a fluorescence intensity of 195 . Calculate the mass of quinine in the original tonic water sample.
The mass of quinine in the original tonic water sample is 37.8 mg.
What is the concentration of the diluted sample?The concentration of the diluted sample with a fluorescence intensity of 73.7 is calculated using the formula of Lambert-Beer's law as follows:
C₁/C₂ = A₁/A₂
where:
C₁ = 25 ppm or 25 mg/L
C₂ = ?
A₁ = 195
A₂ = 73.7
C₂ = 73.7 * 25 / 195
C₂ = 9.45 mg/L
To concentration of the original sample will be determined from the dilution formula:
C₁V₁ = C₂V₂
where;
C₁ = ?
V₁ = 25. 0 mL
C₂ = 9.45 mg/L
V₂ = 200 mL
C₁ = 9.45 * 200 / 25
C₁ = 75.6 mg/L
The volume of the stock sample was 500 mL or 0.5 L
The mass of quinine = 75.6 mg/L * 0.5 L
mass of quinine = 37.8 mg
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What is Kb for the conjugate base of HF (Ka = 6.8 × 10⁻⁴)?
The Kb for the conjugate base of HF, Fluoride ion is 1.470588 * 10^-11
The conjugate base of HF (hydrofluoric acid) is fluoride ion, F-
Ka of HF or hydrofluoric acid is given as 6.8 × 10⁻⁴
Kw = Ka * Kb
Where,
Kb = Base dissociation constant
Kw = Water dissociation constant or equilibrium constant
Ka = Acid dissociation constant
Kw = [H+] [OH-] = 1.0 X 10-14 at room temperature
The formula can be rewritten as,
Kb = (Kw / Ka)
= (10^-14) / (6.8 * 10^-4)
= 1.470588 * 10^-11
Therefore, the kb for the conjugate base of HF, Fluoride ion is 1.470588 * 10^-11
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In paragraph format explain how the energy from Sun gets heats the water in tank. The explanation is based on the concept of atoms (or particles) of matter and the heat transfer (conduction, convection and radiation)
The energy from the sun heats up the water in the tank by convection and radiation.
What is heat transfer?We know that heat is that which is able to effect a temperature change in an object. Now, we know that there are three forms of heat transfer and these are;
1) Conduction
2) Convection
3) Radiation
Now, we know that radiation is the movement of heat without a medium of propagation. Heat from the sun reaches the tank by radiation. The molecules that are at the surface are first heated up and sink down while the heavier particles below move up. This is called convection.
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