Answer:
14.6 g
Explanation:
Fe₂O₃ + 3 C → 2 Fe + 3 CO₃
First, convert grams of Fe₂O₃ to moles. The molar mass is 159.69 g/mol.
(64.6 g)/(159.69 g/mol) = 0.4045 mol
Now, use stoichiometry to convert moles of Fe₂O₃ to moles of C. By looking at the chemical equation, you can see that for every 1 mole of Fe₂O₃, you need 3 moles of C. Use this relationship.
(0.4045 mol Fe₂O₃) × (3 mol C/1 mol Fe₂O₃) = 1.214 mol C
Now, convert moles of C to grams. The molar mass is 12.01 g/mol.
(1.214 mol C) × (12.01 g/mol) = 14.58 g
You need to use significant figures.
14.58 g ≈ 14.6 g
The equilibrium constant, K, for the following reaction is 2.44×10-2 at 518 K: PCl5(g) PCl3(g) + Cl2(g) An equilibrium mixture of the three gases in a 15.3 L container at 518 K contains 0.300 M PCl5, 8.55×10-2 M PCl3 and 8.55×10-2 M Cl2. What will be the concentrations of the three gases once equilibrium has been reestablished, if the equilibrium mixture is compressed at constant temperature to a volume of 8.64 L?
Answer:
[PCl₅] = 0.5646M
[PCl₃] = 0.1174M
[Cl₂] = 0.1174M
Explanation:
In the reaction:
PCl₅(g) ⇄ PCl₃(g) + Cl₂(g)
K equilibrium is defined as:
K = 2.44x10⁻² = [PCl₃] [Cl₂] / [PCl₅]
The initial moles of each compound when volume is 15.3L are:
PCl₅ = 0.300mol/L×15.3L = 4.59mol
Cl₂ = 8.55x10⁻²mol/L×15.3L = 1.308mol
PCl₃ = 8.55x10⁻²mol/L×15.3L = 1.308mol
At 8.64L, the new concentrations are:
[PCl₅] = 4.59mol / 8.64L = 0.531M
[PCl₃] = 1.308mol / 8.64L = 0.151M
[Cl₂] = 1.308mol / 8.64L = 0.151M
At these conditions, reaction quotient, Q, is:
Q = [0.151M] [0.151M] / [0.531M]
Q = 4.29x10⁻²
As Q > K, the reaction will shift to the left producing more reactant, that means equilibrium concentrations are:
[PCl₅] = 0.531M + X
[PCl₃] = 0.151M - X
[Cl₂] = 0.151M - X
Where X is reaction coordinate.
Replacing in K expression:
2.44x10⁻² = [0.151M - X] [0.151M - X] / [0.531M + X]
1.296x10⁻² + 2.44x10⁻²X = 0.0228 - 0.302X + X²
0 = 9.84x10⁻³ - 0.3264X + X²
Solving for X:
X = 0.293 → False solution. Produce negative concentrations
X = 0.0336M → Right solution.
Replacing:
[PCl₅] = 0.531M + 0.0336
[PCl₃] = 0.151M - 0.0336
[Cl₂] = 0.151M - 0.0336
[PCl₅] = 0.5646M[PCl₃] = 0.1174M[Cl₂] = 0.1174MWhich statement is true: Mg -> Mg2+ + 2e-
(1) Mg gains 2 electrons (2) Mg2+ loses 2 electrons (3) mg loses 1 electron (4) mg loses 2 electrons
Answer:
(2) Mg²⁺ loses 2 electrons.
Explanation:
Let's consider the following half-reaction.
Mg ⇒ Mg²⁺ + 2 e⁻
Magnesium is a metal that loses 2 electrons to fulfill the octet rule. When magnesium loses electrons, the oxidation number increases from 0 to +2. This kind of half-reaction is known as oxidation, and has to be accompanied by a reduction of another species.
Consider the 1H NMR spectrum for the following compound:
CH3CH2CH3
Predict the first-order splitting patterns of the indicated proton. This question uses specific splitting patterns instead of the often used generic term "multiplet."
a. doublet of quartets
b. triplet of triplets
c. septet
d. quartet of quartets
e. quintet
Answer:
See explanation
Explanation:
In this case, we have to check the neighbors of each carbon in the molecule. In propane, we have two types of carbons (see figure 1) (blue and red ones). The red carbons are equivalent. (Both have the same neighbors). Now, we can analyze each carbon:
Blue carbon
In the blue carbon, we have 6 hydrogens neighbors (three on each methyl). If we follow the n+1 rule, we will have:
6+1= 7
For the blue carbon, we will have a Septet.
Red carbons
In the red carbon, we have only 2 neighbors (the carbon in the middle only have 2 hydrogens). If we follow the n+1 rule, we will have:
2+1=3
For the red carbon, we will have a triplet.
See figure 2
I hope it helps!
What type of reaction is shown below? Check all
that apply.
AgNO3(aq) + NaCl(aq) → NaNO3(aq) + AgCl(s)
synthesis
decomposition
combustion
single replacement
double replacement
Answer:
double replacement
Explanation:
Double replacement reactions are where both cations and anions of reactants switch.
For eg: AB + CD -----> AD + BC (Here we see both things are replaced)
Synthesis reactions is where two simple things make one complex thing.
So A + B --- > AB
Combustion is usually reaction where Oxygen is reactant but here we don't have that.
Single replacement only replaces either cation or anion.
So AB + C .------> AC + B
Answer:
Replacement
Explanation:
What molar ratio of sodium acetate to acetic acid should be used to prepare a buffer with pH = 4.5? Ka acetic acid = 1.8 x 10-5.
Answer: molar ratio: 0.58
Explanation:
This is a buffer problem. We would use the equation [tex]pH=pKa+log(\frac{base}{acid} )[/tex]. Since we were given Ka and pH, we can find the ratio.
pKa=-log(Ka)
pKa=-log(1.8×10⁻⁵)
pKa=4.74
Now that we have pKa, we can plug in our values and find the molar ratio. Instead of writing base/acid, let's use x.
4.5=4.74+log(x)
-0.24=log(x)
10⁻⁰⁻²⁴=x
x=0.58
3. A student carries out the clay-catalyzed dehydration of cyclohexanol starting with 10 moles of cyclohexanol and obtains 500 mL of pure cyclohexene product. Calculate the student’s percent yield for this reaction. Show your work.
Answer:
[tex]49.45~%[/tex]
Explanation:
In this case, we have to start with the chemical reaction:
[tex]C_6H_1_2O~->~C_6H_1_0~+~H_2O[/tex]
So, if we start with 10 mol of cyclohexanol ([tex]C_6H_1_2O[/tex]) we will obtain 10 mol of cyclohexanol ([tex]C_6H_1_0[/tex]). So, we can calculate the grams of cyclohexanol if we calculate the molar mass:
[tex](6*12)+(10*1)=82~g/mol[/tex]
With this value we can calculate the grams:
[tex]10~mol~C_6H_1_0\frac{82~g~C_6H_1_0}{1~mol~C_6H_1_0}=820~g~C_6H_1_0[/tex]
Now, we have as a product 500 mL of [tex]C_6H_1_0[/tex]. If we use the density value (0.811 g/mL). We can calculate the grams of product:
[tex]500~mL\frac{0.811~g}{1~mL}=405.5~g[/tex]
Finally, with these values we can calculate the yield:
[tex]%~=~\frac{405.5}{820}x100~=~49.45%[/tex]%= (405.5/820)*100 = 49.45 %
See figure 1
I hope it helps!
Based on the data given, the percentage yield of the student's work is 49.45 %.
What is the equation of the reaction?The equation of the clay-catalyzed dehydration of cyclohexanol is given below:
C₆H₁₂O ----> C₆H₁₀ + H₂OFrom the equation of the reaction, 1 mole of cyclohexanol yields 1 mole of cyclohexene.
Therefore 10 moles of cyclohexanol should yield 10 moles of cyclohexene.
What is the moles of cyclohexene obtained?First we determine the mass of cyclohexene obtained.
Mass = density * volume
volume of cyclohexene = 500 mL
density = 0.811 g/mL
mass of cyclohexene = 500 * 0.811
mass of cyclohexene = 405.5 g
Number of moles of cyclohexene = mass/molar mass
molar mass of cyclohexene = 82 g
moles of cyclohexene = 405.5 g/82
moles of cyclohexene = 4.945 moles
What is the percentage yield?Percentage yield = actual yield /expected yield * 100%Percentage yield = 4.945/10 * 100%
Percentage yield = 49.45%
Therefore, the percentage yield of the student's work is 49.45 %.
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Two moles of copper (II) sulfate,CuSO4,contains blank moles of O
Answer:
8 mol
Explanation:
Step 1: Given data
Moles of copper (II) sulfate: 2 mol
Chemical formula of copper (II) sulfate: CuSO₄
Step 2: Establish the molar ratio of copper (II) sulfate to oxygen
According to the chemical formula, the molar ratio of copper (II) sulfate to oxygen is 1:4.
Step 3: Calculate the moles of O in 2 mol of CuSO₄
[tex]2molCuSO_4 \times \frac{4molO}{1molCuSO_4} = 8molO[/tex]
List the following compounds in order from strongest acid to weakest acid. Rank the acids from strongest to weakest.
CH2CHCH2COOH CH2CH2CH2COOH CH3CHCH2COOH CH3CH2CH2COOH
Strongest Weakest
Answer:
CH3CH2CH2COOH<CH2(F)CH2CH2COOH<CH3CH(F)CH2COOH<CH2(F)CH(F)CH2COOH
Explanation:
We know that the presence of highly electronegative elements in carboxylic acid molecules lead to -I inductive effect. This implies that electrons are withdrawn along the chain towards the electronegative element. As electrons are withdrawn towards the electronegative element, the electron cloud of the carbonyl- hydrogen bond in the acid weakens and the hydrogen can now be easily lost as a proton, that is , the molecule becomes more acidic.
The -I inductive effect increases with increase in the number of electronegative elements present in the molecule and the proximity of the electronegative element to the carbonyl group. The closer the electronegative element is to the carbonyl group, the greater the acidity of the molecule since the -I inductive effect dies out with increasing distance from the carbonyl group. Also, the more the number of electronegative elements in the molecule, the greater the - I inductive effect and the greater the acidity of the molecule, hence the answer.
If the charge on the chloride ion is -1, what is the charge on the magnesium ion in the compound MgCl2?
Answer:
+2
Explanation:
Because the charge of the chloride ion is negative, that means that the charge of the magnesium ion must be positive since cations and anions go together, not cation and cation nor anion and anion. Using the "reverse criss-cross method", since the subscript of Mg is 1, that means that this is the lowest whole number ratio so we don't need to worry about simplifying. Therefore, since the charge of Cl is 2, the answer is +2.
The melting point of sodium chloride is 801°C. The melting point of chlorine is -101°C. Explain, in terms of structure and bonding, the difference between the melting points of these two substances.
Answer:
It's harder to melt sodium chloride because of its density and stability.
Explanation:
The bond between Na+ and Cl- is an ionic bond, meaning its an ionic compound. Ionic compounds have more inter molecular forces(forces involving multiple molecules). Chlorine has much less of these forces than NaCl and isn't as dense.
Answer:
It's harder to melt sodium chloride because of its density
Explanation:
4Ga + 3S2 ⇒ 2Ga2S3
How many moles of Sulfur are needed to react with 100.0 grams of Gallium?
Answer:
1.076 mol (corrected to 2 d.p.)
Explanation:
Take the atomic mass of Ga be 69.7.
since no. of moles = mass/ molar mass,
no. of moles of Ga used = 100.0 / 69.7
= 1.43472023 mol
From the balanced equation, the mole ratio of Ga:S2 = 4:3, which means every 4 moles of Ga can react completely with 3 moles of S2.
So, let the no. of moles of Sulphur required be y.
[tex]\frac{4}{3} =\frac{ 1.43472023}{y}[/tex]
4 y = 1.43472023 x 3
y = 1.076 mol (corrected to 2 d.p.)
Chlorine gas can be prepared in the laboratory by the reaction of hydrochloric acid with manganese(IV) oxide.4HCl(aq)+MnO2(s)⟶MnCl2(aq)+2H2O(l)+Cl2(g)A sample of 36.9 g MnO2 is added to a solution containing 48.9 g HCl.What is the limiting reactant?MnO2HClWhat is the theoretical yield of Cl2?theoretical yield:g Cl2If the yield of the reaction is 74.7%, what is the actual yield of chlorine?actual yield:g Cl2
Answer:
HCl is limiting reactant
Theoretical yield: 23.8g Cl₂
Actual yield: 17.6g C₂
Explanation:
Based on the reaction:
4HCl(aq)+MnO2(s)⟶MnCl2(aq)+2H2O(l)+Cl2(g)
4 moles of HCl reacts per mole of MnO₂ to produce 1 mole of MnCl₂ and Cl₂ and 2 moles of water.
To find the limiting reactant you must know the moles of each reactant and knowing that 4 moles of HCl reacts per mole of MnO₂ you can sikve this problem, thus:
Moles HCl (Molar mass: 36.46g/mol): 48.9g ₓ (1mol / 36.46g/mol) =
1.341 moles HCl
Moles MnO₂ (Molar mass: 86.937g/mol): 36.9g ₓ (1mol / 86.937g) =
0.424 moles MnO₂
For a complete reaction of 0.424 moles of MnO₂ you require:
0.424moles MnO₂ ₓ (4 moles HCl / 1 mole MnO₂) = 1.696 moles of HCl.
As you have just 1.341 moles of HCl. HCl is limiting reactant.
Theoretical yield means, in the reaction, that 4 moles of HCl will produce 1 mole of Cl₂. As moles of HCl are 1.341:
1.341 moles HCl ₓ (1 mole Cl₂ / 4 moles HCl) = 0.33525 moles Cl₂
In grams (Molar mass Cl₂: 70.9g/mol):
Theoretical yield: 0.33525 moles Cl₂ ₓ (70.9g / mol) = 23.8g Cl₂
As yield of reaction is 74.7%, the real mass of Cl₂ you obtain (Actual yield) is:
23.8g Cl₂ ₓ 74% = 17.6g C₂
Indicate the types of forces that are involved between the solute and solvent when forming a homogeneous solution between CH3CH2CH2CH2CH3 and CH3CH2CH2CH2CH2CH3.
a. dispersion forces
b. dipole-dipole forces
c. hydrogen bonding
d. ion-dipole forces
2. Indicate the types of forces that are involved between the solute and solvent when forming a homogeneous solution between LiNO3 and H2O.
a. dispersion forces
b. dipole-dipole forces
c. hydrogen bonding
d. ion-dipole forces
Answer:
1) dispersion forces
2) ion-dipole forces
Explanation:
For the formation of a solution of the substances, CH3CH2CH2CH2CH3 and CH3CH2CH2CH2CH2CH3, dispersion forces are involved. Recall that the both are organic substances hence they are both molecular in nature. They are not only molecular, they are nonpolar molecules. This implies that only dispersion forces are the possible intermolecular forces.
For the formation of a solution of LiNO3 and H2O, the dipoles of water interacts strongly with the ions Li^+ and NO3^- thereby separating the ions in solution. The positive dipole of water interacts with NO3^- while the negative dipole of water interacts with Li^+.
Therefore, the interaction between nonpolar molecules is dispersion forces while between polar molecules is ion-dipole forces.
Dispersion forcesIon-dipole forcesDispersion Forces:
They are the weakest form of intermolecular force. The attraction between molecules is temporary.
it is due to temporary assymetric distribution of electrons in the molecules. It is found in the non-polar molecules.For example- Interaction between [tex]\bold { CH_3CH_2CH_2CH_2CH_3 }[/tex] and [tex]\bold { CH_3CH_2CH_2CH_2CH_2CH_3 }[/tex]
Ion-dipole forces:
The attraction between molecules is due to the interaction between opposite ions of molecules.
The distribution of electrons is asymmeric. This interaction is seen between polar molecules.For example- Interaction between [tex]\bold { LiNO_3 }[/tex] and [tex]\bold { H_2O }[/tex]
Therefore, the interaction between nonpolar molecules is dispersion forces while between polar molecules is ion- dipole forces.
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what is the electron configuration of the iodide ion?
A. 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁶4d¹⁰5s²
B. 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁶
C. 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁶4d¹⁰5s²5p⁶
D. 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁶4d¹⁰
Answer:
the answer to this question is C
The electron configuration of the iodide ion is 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁶4d¹⁰5s²5p⁶. The correct option is option C.
What is electron configuration ?The arrangement of an atom's or molecule's electrons in their respective atomic or molecular orbitals is known as its electron configuration; for instance, the electron configuration of the neon atom is 1s2 2s2 2p6.
According to electronic configurations, electrons move individually within each orbital while interacting with the average field produced by all other orbitals. The corrosion potential and reactivity of an atom may be calculated from its electron configuration. The electron configuration of the iodide ion is 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁶4d¹⁰5s²5p⁶.
Therefore, the correct option is option C.
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4
Select the correct answer.
Which of the following describes a compound? (Hint: Carbon and oxygen both appear on the periodic table.)
ОА.
a piece of pure carbon, containing only carbon atoms
OB. oxygen gas surrounding a solid piece of carbon
a substance made of two oxygen atoms for each carbon atom
OD
carbon and oxygen atoms mixed without being bonded together
A 1.00 liter solution contains 0.31 M sodium acetate and 0.40 M acetic acid. If 0.100 moles of barium hydroxide are added to this system, indicate whether the following statements are TRUE or FALSE . (Assume that the volume does not change upon the addition of barium hydroxide.)
a. The number of moles of CH3COOH will remain the same.
b. The number of moles of CH3COO- will increase.
c. The equilibrium concentration of H3O+ will decrease.
d. The pH will decrease.
e. The ratio of [CH3COOH] / [CH3COO-] will remain the same.
Answer and Explanation:
The buffer solution is composed by sodium acetate (CH₃COONa) and acetic acid (CH₃COOH). Thus, CH₃COOH is the weak acid and CH₃COO⁻ is the conjugate base, derived from the salt CH₃COONa.
If we add a strong base, such as barium hydroxide, Ba(OH)₂, the base will dissociate completely to give OH⁻ ions, as follows:
Ba(OH)₂ ⇒ Ba²⁺ + 2 OH⁻
The OH⁻ ions will react with the acid (CH₃COOH) to form the conjugate base CH₃COO⁻.
Initial number of moles of CH₃COOH = 0.40 mol/L x 1 L = 0.40 mol
Initial number of moles of CHCOO⁻= 0.31 mol/L x 1 L = 0.31 mol
moles of OH- added: 2 OH-/mol x 0.100 mol/L x 1 L = 0.200 OH-
According to this, the following are the answers to the sentences:
a. The number of moles of CH₃COOH will remain the same ⇒ FALSE
The number of moles of CH₃COOH will decrease, because they will react with OH⁻ ions
b. The number of moles of CH₃COO⁻ will increase ⇒ TRUE
Moles of CH₃COO⁻ will be formed from the reaction of the acid (CH₃COOH) with the base (OH⁻ ions)
c. The equilibrium concentration of H₃O⁺ will decrease ⇒ FALSE
The equilibrium concentration of OH⁻ is increased
d. The pH will decrease⇒ FALSE
pKa for acetic acid is 4.75. We add the moles of base to the acid concentration and we remove the same number of moles from the conjugate base in the Henderson-Hasselbach equation to calculate pH:
[tex]pH= pKa + log \frac{[conjugate base + base]}{[acid - base]}[/tex]
pH = 4.75 + log (0.31 mol + 0.20 mol)/(0.40 mol - 0.20 mol) = 5.15
Thus, the pH will increase.
When the temperature in a room increases from 25°C to 33°C, changes from a solid to a liquid.
Answer:
true
Explanation:
Because ice melts if the temperature increasese
Answer:
Gallium
Explanation:
edg 2020
A sample of gas is observed to effuse through a pourous barrier in 4.98 minutes. Under the same conditions, the same number of moles of an unknown gas requires 6.34 minutes to effuse through the same barrier. The molar mass of the unknown gas is:________.
g/mol.
Answer:
The molar mass of the unknown gas is [tex]\mathbf{ 51.865 \ g/mol}[/tex]
Explanation:
Let assume that the gas is O2 gas
O2 gas is to effuse through a porous barrier in time t₁ = 4.98 minutes.
Under the same conditions;
the same number of moles of an unknown gas requires time t₂ = 6.34 minutes to effuse through the same barrier.
From Graham's Law of Diffusion;
Graham's Law of Diffusion states that, at a constant temperature and pressure; the rate of diffusion of a gas is inversely proportional to the square root of its density.
i.e
[tex]R \ \alpha \ \dfrac{1}{\sqrt{d}}[/tex]
[tex]R = \dfrac{k}{d}[/tex] where K = constant
If we compare the rate o diffusion of two gases;
[tex]\dfrac{R_1}{R_2}= {\sqrt{\dfrac{d_2}{d_1}}[/tex]
Since the density of a gas d is proportional to its relative molecular mass M. Then;
[tex]\dfrac{R_1}{R_2}= {\sqrt{\dfrac{M_2}{M_1}}[/tex]
Rate is the reciprocal of time ; i.e
[tex]R = \dfrac{1}{t}[/tex]
Thus; replacing the value of R into the above previous equation;we have:
[tex]\dfrac{R_1}{R_2}={\dfrac{t_2}{t_1}}[/tex]
We can equally say:
[tex]{\dfrac{t_2}{t_1}}= {\sqrt{\dfrac{M_2}{M_1}}[/tex]
[tex]{\dfrac{6.34}{4.98}}= {\sqrt{\dfrac{M_2}{32}}[/tex]
[tex]M_2 = 32 \times ( \dfrac{6.34}{4.98})^2[/tex]
[tex]M_2 = 32 \times ( 1.273092369)^2[/tex]
[tex]M_2 = 32 \times 1.62076418[/tex]
[tex]\mathbf{M_2 = 51.865 \ g/mol}[/tex]
Which is not a compound? A.They are substances B. They have compositions that vary C. They can be physically separated into their component Elements. D. They have properties similar to those of their component elements.
Answer:
D.They have properties similar to those of their component elements.
Explanation:
When elements are joined, the atoms lose their individual properties and have different properties from the elements they are made of .
A 23.0% by mass LiCl solution is prepared in water. What is the mole fraction of the water? 0.113 0.887 0.873 0.127 0.911
Answer: The Answer should be B. 0.887 (:
Explanation:
The mole fraction of the solution is 0.887.
Mass percent of LiCl present = 23.0%
Mass of the LiCl can be obtained from;
23 = x/100 × 100/1
x = 23 g
Number of moles of LiCl = 23g/42 g/mol = 0.55 moles
Number of moles of water = (100 - 23) g/18 g/mol = 4.3 moles
Total number of moles = 0.55 + 4.3 = 4.85 moles
Mole fraction of water = 4.3 moles/4.85 moles = 0.887
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The rate at which two methyl radicals couple to form ethane is significantly faster than the rate at which two tert-butyl radicals couple. Offer two explanations for this observation.
Answer:
1. stability factor
2. steric hindrance factor
Explanation:
stability of ethane is lesser to that of two tert-butyl, so ethane will be more reactive and faster.
ethane is less hindered and more reactive, while two tert-butyl is more hindered and less reactive
how many moles of ions are produced by ionization of 2 moles of MgCl2
Answer:
number of ions = 12.04 x 10^²³
Explanation:
n = number of ions/Avogadro's constant
2 = number of ions/6.02 x 10^²³
number of ions= 2 x 6.02 x 10^²³
number of ions = 12.04 x 10^²³
A student followed the procedure of this experiment to determine the percent NaCl in a commercial bleaching solution that was found in the basement of an abandoned house. The student diluted 50.00 mL of the commercial bleaching solution to 250 mL in a volumetric flask, and titrated a 20-ml aliquot of the diluted bleaching solution. The titration required 35.46 mL of 0.1052M Na S,O, solution. A faded price label on the gallon bottle read $0.79. The density of the bleaching solution was 1.10 g ml.
(1) Calculate the mass of commercial bleaching solution titrated. 1.1 450=559
(2) Determine the percent NaOCl in the commercial bleaching solution.
(3) Calculate the mass of one gallon of the commercial bleaching solution.
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1. How many hydrogen atoms are in an alkane that has 7 carbon atoms?
2. An alkane contains 18 H atoms. Name the compound.
Answer:
1- there are 16 hydrogen atoms. ( heptane C7H16)
2- The compound is octane (C8H18)
explanation
to determine any atom in an alkane, this formula is used Cn H 2n +2, where n is the number of carbon atoms in the molecule.
to find the compound in Q2 we'll apply the numbers:
C nH₂n+2
Calculate the pH of a solution that has [H3O+]=4.3 x 10^-5 M
Answer:
pH = 4.4
Explanation:
pH = -log[H₃O⁺]
= -log(4.3 × 10⁻⁵)
pH = 4.37 = 4.4
I'm actually learning this in my chemistry class right now lol. Hope this helps though. :)
HELPPP.
Which of the following is a property of matter?
O A. It takes up space.
OB. It is everywhere.
O C. It is constantly changing.
O D. It cannot be divided.
Answer:
a
Explanation:
Matter can be volume or density. So, this concludes that it is when it takes up space.
Answer: A.
Explanation:
it takes up space
What is the core charge of helium and why?
Answer:
Formula for effective nuclear charge is as follows. So, for He atom value of S = 0.30 because the electrons are present in 1s orbital. Therefore, calculate the effective nuclear charge for helium as follows. Thus, we can conclude that the effective nuclear charge for helium is 1.7
Explanation:
The effective nuclear charge experienced by a 1s electron in helium is +1.70.
What volume of CH4(g), measured at 25oC and 745 Torr, must be burned in excess oxygen to release 1.00 x 106 kJ of heat to the surroundings
Answer:
[tex]V=27992L=28.00m^3[/tex]
Explanation:
Hello,
In this case, the combustion of methane is shown below:
[tex]CH_4+2O_2\rightarrow CO_2+2H_2O[/tex]
And has a heat of combustion of −890.8 kJ/mol, for which the burnt moles are:
[tex]n_{CH_4}=\frac{-1.00x10^6kJ}{-890.8kJ/mol}= 1122.6molCH_4[/tex]
Whereas is consider the total released heat to the surroundings (negative as it is exiting heat) and the aforementioned heat of combustion. Then, by using the ideal gas equation, we are able to compute the volume at 25 °C (298K) and 745 torr (0.98 atm) that must be measured:
[tex]PV=nRT\\\\V=\frac{nRT}{P}=\frac{1122.6mol*0.082\frac{atm*L}{mol*K}*298K}{0.98atm}\\\\V=27992L=28.00m^3[/tex]
Best regards.
When 13.6 g of calcium chloride, CaCl2, was dissolved in 100.0 mL of water in a coffee cup calorimeter, the temperature rose from 25.00 °C to 31.75 °C. Determine the ∆Hrxn in kJ/mol for the reaction as written below. Assume that the density of the solutions is 1.000 g/mL, and that the specific heat capacity of the solutions is that of pure water. Must show your work (scratch paper) to receive credit.
Answer:
THE ENTHALPY OF SOLUTION IS 3153.43 J/MOL OR 3.15 KJ/MOL.
Explanation:
1. write out the variables given:
Mass of Calcium chloride = 13.6 g
Change in temperature = 31.75°C - 25.00°C = 6.75 °C
Density of the solution = 1.000 g/mL
Volume = 100.0 mL = 100.0 mL
Specific heat of water = 4.184 J/g °C
Mass of the water = unknown
2. calculate the mass of waterinvolved:
We must first calculate the mass of water in the bomb calorimeter
Mass = density * volume
Mass = 1.000 * 100
Mass = 0.01 g
3. calculate the quantity of heat evolved:
Next is to calculate the quantity of heat evolved from the reaction
Heat = mass * specific heat of water * change in temperature
Heat = mass of water * specific heat *change in temperature
Heat = 13.6 g * 4.184 * 6.75
Heat = 13.6 g * 4.184 J/g °C * 6.75 °C
Heat = 384.09 J
Hence, 384.09J is the quantity of heat involved in the reaction of 13.6 g of calcium chloride in the calorimeter.
4. calculate the molar mass of CaCl2:
Next is to calculate the molar mas of CaCl2
Molar mass = ( 40 + 35.5 *2) = 111 g/mol
The number of moles of 13.6 g of CaCl2 is then:
Number of moles of CaCl2 = mass / molar mass
Number of moles = 13.6 g / 111 g/mol
Number of moles = 0.1225 mol
So 384.09 J of heat was involved in the reaction of 1.6 g of CaCl2 in a calorimter which translates to 0.1225 mol of CaCl2..
5. Calculate the enthalpy of solution in kJ/mol:
If 1 mole of CaCl2 is involved, the heat evolved is therefore:
Heat per mole = 384.09 J / 0.1225 mol
Heat = 3 135.43 J/mol
The enthalpy of solution is therefore 3153.43 J/mol or 3.15 kJ/mol.
You use 10.0 mL of solution A, 10.0 mL of solution B, and 70.0 mL of water for your first mixture. What is the initial concentration of KIO3
Complete Question
The complete question is shown on the first uploaded image
Answer:
The initial concentration is [tex]C_f = 0.0022 \ M[/tex]
Explanation:
From the question we are told that
The volume of solution A is [tex]V_i = 10.0 mL[/tex]
The concentration of A is [tex]C_i = 0.0200 \ M[/tex]
The volume of solution B is [tex]V_B = 10.0mL[/tex]
The volume of water is [tex]V_{w } = 70.0 mL[/tex]
Generally the law of dilution is mathematically represented as
[tex]C_i * V_i = C_f * V_f[/tex]
Where [tex]C_f[/tex] is the concentration of the mixture
[tex]V_f[/tex] is the volume of the mixture which is mathematically evaluated as
[tex]V_f = 10 + 10 + 70[/tex]
[tex]V_f = 90mL[/tex]
So
[tex]C_f = \frac{C_i * V_i}{ V_f}[/tex]
substituting values
[tex]C_f = \frac{0.0200 * 10 }{90}[/tex]
[tex]C_f = 0.0022 \ M[/tex]
Note the mixture obtained is [tex]KIO_3[/tex]