Answer:
[tex]Q=4154J[/tex]
Explanation:
Hello,
In this case, the involved heat in this heating process is considered to be computed via:
[tex]Q=nCp\Delta T[/tex]
Whereas we assume a constant molar specific heat of helium which is 20.77 J/(mol*K), thus, the transferred energy in the form of heat turns out:
[tex]Q=2mol*20.77\frac{J}{mol*K} *100K\\\\Q=4154J[/tex]
Regards.
The basic function of a carburetor of an automobile is to atomize the gasoline and mix it with air to promote rapid combustion. As an example, assume that 30 cm3 of gasoline is atomized into N spherical droplets, each with a radius of 2.0 × 10−5 m. What is the total surface area of these N spherical droplets? Answer: [A] m2.
Answer:
The total surface area of these N spherical droplets is 4.4929 m²
Explanation:
From the information given :
assuming that :
30 cm³ of gasoline is atomized into N spherical droplets &
each with a radius of 2.0 × 10−5 m
We are tasked to determine the total surface area of these N spherical droplets
We all known that:
[tex]1 \ cm^3 = 10 ^{-6} m^3[/tex]
Therefore
[tex]30 \ cm^3 = 30 * 10 ^{-6} m^3 = 3 *1 0^{-5} \ m^3[/tex]
For each droplet; there is a required volume which is = [tex]\dfrac{4}{3} \pi r ^3[/tex] since it assumes a sphere shape .
Thus;
replacing radius(r) with 2.0 × 10−5 m; we have:
[tex]= \dfrac{4}{3} \pi * (2.0 *10^{-5} m) ^3[/tex]
= [tex]3.35 * 10^{-14} \ m^3[/tex]
However; there are [tex]3*10^{-5} \ m^3[/tex] gasoline atomized into N spherical droplets with each with radius 2.0 × 10−5 m
For N ; we have ;
[tex]=\dfrac{3*10^{-5} \ m^3}{3.35 * 10^{-14} \ m^3/ droplet}[/tex]
= [tex]8.95*10^8 \ droplet s[/tex]
So; each droplet have a surface area = [tex]4 \pi r^2[/tex]
= [tex]4 \pi (2.0*10^{-5}m) ^2[/tex]
= [tex]5.02*10^{-9} \ m^2/droplets[/tex]
The surface area per droplet is equivalent to [tex]5.02*10^{-9} \ m^2/droplets[/tex]
Thus;
The total surface area of these N spherical droplets will be :
= [tex]8.95*10^8 \ droplet s * 5.02*10^{-9} \ m^2/ droplets[/tex]
= 4.4929 m²
The total surface area of these N spherical droplets is 4.4929 m²
If an electromagnetic wave has a frequency of 4.5 x 10^18 Hz, what is its wavelength? The speed of light is 3 x 108 m/s.
Answer:
Wavelength, λ = 6.7 x 10^-11 m
Explanation:
Frequency and wavelength are inversely proportional to each other.
In this problem;
f = 4.5 x 10^18 Hz
wavelength, λ = ?
Speed of light, c = 3 x 108 m/s.
These variables are related by the following equation;
c = λ * f
Making λ subject of focus, we have;
λ = c / f
λ = 3 x 10^8 / 4.5 x 10^18
λ = 0.67 x 10^-10
λ = 6.7 x 10^-11 m
At a temperature of 393 K, the pressure of a sample of nitrogen is 1.07 atm. What will the pressure be at a temperature of 478 K? (Assume constant volume)
Answer:
1.30atm
Explanation:
P1/T1 = P2/T2
1.07/393 = P2/478
Answer: the first one is correct
Explanation:
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The two reactions above, show routes for conversion of an alkene into an oxirane. If the starting alkene is cis-3-hexene the configurations of the oxirane products, A and B are Product A: _______ Product B: _______ Will either of these two oxirane products rotate the plane of polarization of plane polarized light? _____
Answer:
Product A: cis; no
Product B: cis: no
Explanation:
Two common methods of forming oxiranes from alkenes are:
Reaction with peroxyacids Formation of a halohydrin followed by reaction with base
1. Reaction with peroxyacids
(a) Stereochemistry
The reaction with a peroxyacid is a syn addition, so the product has the same stereochemistry as the alkene.
The starting alkene is cis, so the product is cis-2,3-diethyloxirane.
(b) Configuration
The product is optically inactive because it has an internal plane of symmetry.
It will not rotate the plane of polarized light.
2. Halohydrin formation
(a) Stereochemistry
The halogenation of the alkene proceeds via a cyclic halonium ion.
The backside displacement of halide ion by alkoxide is also stereospecific, so a cis alkene gives a cis epoxide.
The product is cis-2,3-diethyloxirane.
(b) Configuration
The cyclic halonium ion has an internal plane of symmetry, as does the product (meso).
The oxirane will not rotate the plane of polarized light.
(a) How many stereoisomers are possible for 4-methyl-1,2-cyclohexanediol? ___ (b) Name the stereoisomers formed by oxidation of (S)-4-methylcyclohexene with osmium tetroxide. If there is only one stereoisomer formed, leave the second space blank. Isomer #1: Isomer #2: (c) Is the product formed in step (b) optically active? _____
Answer:
See explanation
Explanation:
For the first part of the question, we have to check the chiral carbons in 4-methyl-1,2-cyclohexanediol. In this case carbons, 1 and 2 are chiral, if we have 2 chiral carbons we will have 4 isomers. We have to remember that formula 2^n in which "n" is the number of chiral carbons, so:
2^n = 2^2 = 4 isomers
And the isomers that we can have are:
1) (1R,2S)-4-methylcyclohexane-1,2-diol
2) (1S,2S)-4-methylcyclohexane-1,2-diol
3) (1S,2S)-4-methylcyclohexane-1,2-diol
4) (1S,2R)-4-methylcyclohexane-1,2-diol
See figure 1
For the second part of the question, we have to remember that the oxidation with [tex]OsO_4[/tex] is a syn addition. In other words, the "OHs" are added in the same plane. In this case, we have the methyl group with a wedge bond, so the "OH" groups will have a dashed bond due to the steric hindrance. Due to this we only can have 1 isomer ((1S,2R,4S)-4-methylcyclohexane-1,2-diol). Finally, on this molecule, we dont have any symmetry planes (this characteristic will cancel out the optical activity), so the product of this reaction has optical activity.
See figure 2
I hope it helps!
A 3.00-g sample of an alloy (containing only Pb and Sn) was dissolved in nitric acid (HNO3). Sulfuric acid was added to this solution, which precipitated 2.93 g of PbSO4. Assuming that all of the lead was precipitated, what is the percentage of Sn in the sample? (molar mass of PbSO4 = 303.3 g/mol)
Answer:
33.3% of Sn in the sample
Explanation:
The addition of SO₄⁻ ions produce the selective precipitation of Pb²⁺ to produce PbSO₄.
Moles of PbSO₄ (molar mass 303.26g/mol) in 2.93g are:
2.93g ₓ (1mol / 303.26) = 9.66x10⁻³ moles PbSO₄ = Moles Pb²⁺.
As molar mass of Pb is 207.2g/mol, mass in 9.66x10⁻³ moles of Pb²⁺ is:
9.66x10⁻³ moles of Pb²⁺ ₓ (207.2g / mol) = 2.00g of Pb²⁺
As mass of the sample is 3.00g, mass of Sn²⁺ is 3.00g - 2.00g = 1.00g
And the percentage of Sn in the sample is:
1.00g / 3.00g ₓ 100 =
33.3% of Sn in the sampleResources Use the exothermic and endothermic interactive to classify the solution process for each solute. Exothermic solution process Endothermic solution process
KOH CaCl, NaCT NaOH NaNO, NH NO,
Answer:
Exothermic interractive are the following: NaOH, KOH, CaCl₂
Endothermic interactive are the following: NaCl, NH₄NO₃, NaNO₃
Explanation:
NaOH, KOH, and CaCl2 are exothermic reactants. NaCl, NH4NO3, and NaNO3 are endothermic interacting substances.
Endothermic reactions: what are they?Chemical processes that can release or absorb energy are referred to as endothermic. In endothermic reactions, more energy is used when bonds in the reactants are broken than is released when new bonds are formed in the products.
How do endothermic processes take place?When the temperature of the an isolated system drops while the surroundings of the a non-isolated system warm up, this is known as an endothermic response. The heat of reaction is generally positive in endothermic processes (qrxn>0).
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Question 4
2 pts
A careless chemistry student performed a chemical reaction where his theoretical yield of
Magnesium oxide was 57.82 grams, but he actually produced 12.89 grams. What is his percent yield
for this experiment? (include the number with 4 significant figures but no units)
Answer:
22.29%
Explanation:
Percent yield = experimental yield / theoretical yield * 100
= 12.89 / 57.82 * 100 = 22.29%
The lock and key model and the induced fit model are two models of enzyme action explaining both the specificity and the catalytic activity of enzymes. Indicate whether each statement is part of the lock and key model, the induced fit model, or is common to both models.
a. Enzyme conformation changes when it binds the substrate so the active site fits the substrate
b. Substrate binds to the enzyme at the active site, forming an enzyme-substrate complex
c. Enzyme active site has a rigid structure complementary
d. Substrate binds to the enzyme through noncovalent interactions
Answer:
"The active site of the enzyme has a complementary rigid structure" belongs to the key and lock system
"The conformation of the enzyme changes when it binds to the substrate so that the active site conforms to the substrate." belongs to the induced fit system.
"The substrate binds to the enzyme at the active site, forming an enzyme-substrate complex" belongs to both, that is, the key and lock system and the induced fit system.
"The substrate binds to the enzyme through non-covalent interactions" can belong to both enzyme systems.
Explanation:
Enzymatic key and lock systems bear this name because the enzyme at its site of union with the substrate has an ideal shape so that its fit is perfect, similar to a headbreaker, so once they are joined they are not It can bind another substrate to the enzyme, since they are generally associated with strong chemical bonds.
The shape of the enzyme's active site is a negative of what the shape of the substrate would be.
On the other hand, in the mechanism or enzyme system of induced adjustment, the enzyme has an active site that is where it binds with the substrate and another site where another chemical component binds, which when this chemical component binds this enzyme changes its morphology and becomes "active" to bond with your substrate.
This happens a lot in the inactive enzymes that are usually activated in digestive processes since the fact that these enzymes are constantly active would be dangerous, therefore the body takes the induced enzyme system as a control mechanism, where a molecule or chemical compound induces change morphological of an enzyme by means of the allosteric union so that it joins its substrate and catalyzes or analyzes it, depending on the enzymatic character of the enzyme.
Drag the description to the category
Answer:
ok
Explanation:
A gas contained in a steel tank has a volume of 1.5 L at a temperature of 390 K. What will be the volume when the temperature changes to 1470C? Group of answer choices
Answer:
1.5 L
Explanation:
If the gas is contained in a steel tank, the volume will remain constant when the temperature changes.
The volume will be 1.5 L.
You've just synthesized a new molecule and need to purify it by recrystallization. You find that it is poorly soluble in water and highly soluble in ethanol, even when cooled in ice. What solvent should work in this situation
Answer:
Water is used as a solvent.
Explanation:
In order to purify the new molecule, recrystallization occurs in which the new molecule should be added in water and heated the water in order to increase the solubility of the solution. The new molecule dissolve in water while the impurity remains undissolved which can be removed from the solution and then remain the solution to be cold down and the new molecule will again undissolved and the molecule can be extracted without any impurities. We use water instead of ethanol due to lower solubility.
A solid white substance A is heated strongly in the absence of air. It decomposes to form a new white substance B and a gas C. The gas has exactly the same properties as the product obtained when carbon is burned in an excess of oxygen. Based on these observations, can we determine whether solids A and B and the gas C are elements or compounds?
Answer:
A, B and C are compounds
Explanation:
First of all, I need to establish that when carbon is burnt in excess oxygen, carbon dioxide is obtained as shown by this equation; C(s) + O2(g) ----> CO2(g).
Looking at the presentation in the question, A was said to be heated strongly and it decomposed to B and C. Only a compound can decompose when heated. Elements can not decompose on heating. Secondly, compounds usually decompose to give the same compounds that combined to form them. Compounds hardly decompose into their constituent elements.
Again from the information provided, the compound A is a white solid. This is likely to be CaCO3. It decomposes to give another white solid. This may be CaO and the gas was identified as CO2.
Hence;
CaCO3(s)--------> CaO(s) + CO2(g)
A sample of magnesium ribbon is ignited in a crucible to form magnesium oxide. Determine the empirical formula of magnesium oxide from the following data:
mass of crucible and cover + magnesium metal
33.741 g
mass of crucible and cover
33.500 g
mass of crucible and cover + magnesium oxide
33.899 g
Answer:
MgO
Explanation:
The following data were obtained from the question:
mass of crucible and cover + magnesium metal = 33.741 g
mass of crucible and cover = 33.5 g
mass of crucible and cover + magnesium oxide = 33.899 g
Next, we shall determine the mass of magnesium metal. This can be obtained as follow:
mass of crucible and cover + magnesium metal = 33.741 g
mass of crucible and cover = 33.5 g
Mass of magnesium metal =..?
Mass of magnesium metal = (mass of crucible and cover + magnesium metal) – (mass of crucible and cover)
Mass of magnesium metal = 33.741 – 33.5
Mass of magnesium metal = 0.241g
Next, we shall determine the mass of magnesium oxide. This can be obtained as follow:
mass of crucible and cover + magnesium oxide = 33.899 g
mass of crucible and cover = 33.5 g
Mass of magnesium oxide =?
Mass of magnesium oxide = (mass of crucible and cover + magnesium oxide) – (mass of crucible and cover)
Mass of magnesium oxide = 33.899 –. 33.5
Mass of magnesium oxide = 0.399g
Next, we shall determine the mass of oxygen. This can be obtained as follow:
Mass of magnesium oxide = 0.399g
Mass of magnesium metal = 0.241g
Mass of oxygen =..?
Mass of oxygen = (Mass of magnesium oxide) – (Mass of magnesium metal)
Mass of oxygen = 0.399 – 0241
Mass of oxygen = 0.158g
Now, we can obtain the empirical formula for the magnesium oxide as follow:
Mg = 0.241g
O = 0.158g
Divide by their molar mass
Mg = 0.241 / 24 = 0.01
O = 0.158 / 16 = 0.0099
Divide by the smallest
Mg = 0.01 / 0.0099 = 1
O = 0.0099 / 0.0099 = 1
Therefore, the empirical formula for the magnesium oxide is MgO
What energy transfer happens when wood is burning?
Answer:
Mechanical to Heat
explanation:
The wood itself can make mechanical energy but when it's on fire it makes heat energy
Answer: Chemical to heat and light
Explanation: The energy transforms from chemical energy to heat and light energy. Because when the candle burns a chemical reaction occurs and produces heat and light.
What is the rate constant of a reaction if rate = 1.5 (mol/L)/s, [A] is 1 M, [B] is
3 M, m = 2, and n = 1?
k=
rate
[A]" [B]"
A. 0.17
B. 13.5
C. 0.5
D. 4.5
[tex]\mathfrak{\huge{\pink{\underline{\underline{AnSwEr:-}}}}}[/tex]
Actually Welcome to the Concept of the Rate Constant.
Here, the "K" is the Rate Constant.
so the ANSWER IS C.) 0.5
The rate of constant is 0.5.
The answer is option C.
How do find the rate of constant?To determine the fee regulation from a desk, you have to mathematically calculate how differences in molar concentrations of reactants affect the response charge to parent out the order of every reactant. Then, plug in values of the response charge and reactant concentrations to discover the particular rate constant.
What's the rate of constant?The particular rate constant is the proportionality steady touching on the rate of the reaction to the concentrations of reactants. The fee regulation and the unique charge constant for any chemical response need to be decided experimentally. The price of the fee regular is temperature-established.
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How many grams of LiNO3 must be added to 25.0 g of water to prepare a 5.00% (m/m) solution of LiNO3?
Answer:
1.25 g.
Explanation:
5% or 25 g
= 0.05 * 25
= 1.25 g (answer).
A compound consisting of atoms of small atomic mass is more likely to require what
Answer:
a lower temperature to liquefy
Explanation:
Lewis structure of methyl metcaptain
Answer:
The lewis structure of the compounds can be drawn by making the skeleton of the molecule first. Then the different atoms are arranged and the electrons are arranged in their bonding pattern. The lone pair of the atoms, which are not involved in the bonding are represented by the dots.
So the lewis structures of both the compound methyl mercaptan has been in the attached image:
Spelling of methyl metcaptain is wrong, the correct spelling is methyl mercaptan.
Answer:
Methyl mercaptan is also known as Methanethiol with the chemical formula CH3SH and it is an organosulfur compound.
For lewis structure of methyl mercaptan (CH3SH), there are total 14 valence electrons. Four hydrogen atoms has one valence electron each, carbon has four valence electrons and sulfur has six valence electrons. Carbon form one bond with three hydrogen atoms by sharing one electron with each, carbon form one single bond with sulfur atom by sharing one electron with it and sulfur form one single bond with hydrogen. Sulfur left with four unpair electrons.
g Which statement is incorrect regarding oxidation? Oxidation is a "gain" of electrons. Oxidation is the combination with O atoms. Oxidation is an increase in oxidation state. Oxidation is always accompanied by reduction. none of these
Answer:
The incorrect statement from the options is OXIDATION IS A "GAIN" OF ELECTRONS
Explanation:
Oxidation in a redox reaction is the loss of electrons. It is also the increase in the oxidation states of an atom or ion or atoms in a molecule. A redox reaction is a type of chemical reaction in which there is a transfer of electrons from an atom or ion to another resulting in a change in oxidation states of the substances involved. The reducing agent in the reaction is undergoes oxidation by losing electrons while the oxidating agent is reduced that is it gains electrons at the end of the reaction. The atom or ion from which electron is lost is said to be oxidized while the other atom or ion involved in the reaction is reduced.
Oxidation is also the combination with O atoms and it is always accompanied by reduction because oxidation forms a half of the whole redox reaction. A substance cannot be oxidized except it has reduced another substance by losing electrons to it.
The mathematics of combining quantum theory with wave motion of atomic particles is known as _____.
Combining quantum theory with wave motion of atomic particles is: Wave Mechanics
At a certain temperature this reaction follows second-order kinetics with a rate constant of 0.00317sâ1: 2N2O5(g) â2N2O4(g) + O29(g) Suppose a vessel contains SO3 at a concentration of 1.44M . Calculate the concentration of SO3 in the vessel 0.240 seconds later. You may assume no other reaction is important.Round your answer to 2 significant digits.
Answer:
[A] = 1.438M = 1.4M (Two s.f)
Explanation:
Rate constant, k = 0.00317
Initial Concentration, [A]o = 1.44M
Final Concentration, [A] = ?
Time, t = 0.240 s
Since this is a second order reaction, the formula for this is given as;
1 / [A] = 1 / [A]o + kt
1 / [A] = 1 / 1.44 + (0.00317 * 0.240)
1 / [A] = 0.6944 + 0.0007608
1 / [A] = 0.6952
[A] = 1.438M = 1.4M (Two s.f)
What is the product(s) of the reaction below?
2Al(s) + Fe2O3(s) Al2O3(s) + 2Fe(s)
A. Solid aluminum oxide and solid iron
B. Solid aluminum
C. Saturated aluminum oxide and saturated iron
D. Iron(III) oxide and aluminum oxide
Answer:
I would put A
Explanation:
A new substance is produced as a result of a chemical reaction in which bonds between the molecules of the reactant and product are broken and new bonds are formed. Here the products are Al₂O₃ and Fe. The correct option is A.
Chemical reactions are interactions between two or more molecules that result in the production of new products. Products, as opposed to reactants, are compounds that result from an interaction between two other substances.
The reactants are on the left, while the products that are created are on the right. A one-headed or two-headed arrow connects the reactants and products.
Thus the correct option is A.
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How many water molecules are in a block of ice containing 1.25 mol of water (H2O)
Answer:
Molecules = 7.5 × 10²³ molecules
Explanation:
Given:
Moles = 1.25 mol
Avogadro's No. = [tex]N_{A}[/tex] = 6.022 * 10²³
Required:
Molecules = ?
Formula:
Molecules = Moles × [tex]N_{A}[/tex]
Solution:
Molecules = 1.25 × 6.022 × 10²³
Molecules = 7.5 × 10²³ molecules
Identify the precipitation reaction in the set?
Answer:
The third reaction
(2NaOH + NiCL2 ---> 2NaCl + Ni(OH)2)
Explanation:
By definition, a precipitation reaction refers to the formation of an insoluble salt when two solutions containing soluble salts are combined.
(Source: lumenlearning)
From the 4 options, we can eliminate the first and second one immediately because there is no formation of an insoluble salt.
Then, the last one can also be eliminated because even though there is insoluble solid formed, but it is not a salt, and, the reactants are not solutions too. In fact, the last one is a displacement reaction. A more reactive metal displaces a less reactive metal to form an ion.
Since the third reaction matches the definition of precipitation reaction, this is the answer.
A chemist observed an unknown Balmer Series decay through an emission of 410 nm. Using the experimental wavelength, determine the energy levels transition involved in the
emitted wavelength.
Answer:
Option D is correct.
n = 6 to n = 2
Explanation:
Like all waves emitted from the movement of electrons from one energy level to another, the wavelength (λ) is given by the equation involving Rydberg's constant
(1/λ) = Rₕ [(1/n₂²) - (1/n₁²)]
where Rₕ = 10973731.57 m⁻¹ = (1.0974 × 10⁷) m⁻¹
n₂ = principal quantum number corresponding to the final energy level of the electron = 2 (For Balmer Series)
n₁ = principal quantum number corresponding to the final energy level of the electron = ?
λ = 410 nm = (410 × 10⁻⁹) m
(1/λ) = (2.439 × 10⁶) m⁻¹
2.439 × 10⁶ = (1.0974 × 10⁷) [(1/2²) - (1/n₁²)]
0.25 - (1/n₁²) = (2.439 × 10⁶) ÷ (1.0974 × 10⁷) = 0.2222602562
(1/n₁²) = 0.25 - 0.2222602562 = 0.0277397438
n₁² = (1/0.0277397438) = 36.05
n₁ = 6
Hope this Helps!!!
Write the empirical formula
Answer:
[tex]Pb(CO_{3})_{2} \\Pb(NO_{3})_{4} \\FeCO_{3}\\Fe(NO_{3})_{2}[/tex]
Explanation:
[tex]Pb^{4+}(CO_{3}^{2-})_{2} --->Pb(CO_{3})_{2} \\Pb^{4+} (NO_{3}^{-})_{4} --->Pb(NO_{3})_{4} \\Fe^{2+} CO_{3}^{2-} --->FeCO_{3}\\Fe^{2+} (NO_{3}^{-})_{2}--->Fe(NO_{3})_{2}[/tex]
What would the cathode be in a nickel and copper electrolytic cell
Answer:
d
Explanation:
Morphine, C 17H 19NO 3, is often used to control severe post-operative pain. What is the pH of the solution made by dissolving 25.0 mg of morphine in 100. mL of water? (For morphine, K b = 1.62 × 10 –6.)
Answer:
pH = 9.58
Explanation:
First of all, we need to determine the molarity of the solution.
We determine the molar mass of morphine:
12g/m . 17 + 1 g/m . 19 + 14 g/m + 16 g/m . 3 = 285.34 g/m
molar mass g/m, is the same as mg/mm
25 mg . 1 mmol / 285.34 mg = 0.0876 mmoles / 100 mL = 8.76×10⁻⁴ M
In diltuted solution, we must consider water.
Mass balance for morphine = [Morphine] + [Protonated Morphine]
8.76×10⁻⁴ M = [Morphine] + [Protonated Morphine]
As Kb is too small, I can skipped, the [Protonated Morphine]
8.76×10⁻⁴ M = [Morphine]
In the charge balance I will have:
[OH⁻] = [H⁺ morphine] + [H⁺]
Let's go to the Kb expression
Morphine + H₂O ⇄ MorphineH⁺ + OH⁻ Kb
Kb = [MorphineH⁺] [OH⁻] / [Morphine]
Kb = [MorphineH⁺] [OH⁻] / 8.76×10⁻⁴ M
So now, we need to clear [MorphineH⁺] to replace it in the charge balance
Kb . 8.76×10⁻⁴ M / [OH⁻] = [MorphineH⁺]
Now, the only unknown value is the [OH⁻]
[OH⁻] = Kb . 8.76×10⁻⁴ M / [OH⁻] + Kw/[OH⁻]
Remember that Kw = [H⁺] . [OH⁻]
[H⁺] = Kw/[OH⁻]
[OH⁻]² = 1.62×10⁻⁶ . 8.76×10⁻⁴ + 1×10⁻¹⁴
[OH⁻] = √(1.62×10⁻⁶ . 8.76×10⁻⁴ + 1×10⁻¹⁴)
[OH⁻] = 3.76×10⁻⁵ → - log [OH⁻] = pOH = 4.42
pH = 14 - pOH → 14 - 4.42 = 9.58
What is the molarity of a solution that is 7.00% by mass magnesium sulfate and has a density of 1.071 g/mL?
Answer:
0.623 M
Explanation:
Step 1: Given data
Percent by mass (%m/m): 7.00 %Density of the solution (ρ): 1.071 g/mLMolar mass of magnesium sulfate: 120.37 g/molStep 2: Calculate the percent by volume (%m/v)
We will use the following expression.
[tex]\%m/v = \%m/m \times \rho = 7.00\% \times 1.071g/mL = 7.50g\%mL[/tex]
Step 3: Calculate the molarity
7.50 g of magnesium sulfate are dissolved in 100 mL of the solution. The molarity is:
[tex]M = \frac{7.50g}{120.37g/mol \times 0.100L } = 0.623 M[/tex]