Calculate the pOH for the following:
1. [H+] = 1 x 10-12 M
2. [OH-] = 1 x 10-6 M
3. [H+] = 1 x 10-1 M
4. [H+] = 1 x 10-4 M
5. [OH-] = 1 x 10-7 M
The pOH refers to the negative logarithm of the hydroxide concentration.
What is the pOH?The term pOH refers to the negative logarithm of the hydroxide concentration. Now we know that there is a relation that states that;
[H+] [OH-] = 1 * 10^-14
We shall now apply this relation in each case as follows;
[OH-] = 1 * 10^-14/1 x 10-12
[OH-] = 1 * 10^-2
pOH = 2
2. pOH = -log( 1 x 10-6 M) = 6
3. [OH-] = 1 * 10^-14/ 1 x 10-1
[OH-] = 1 * 10^-13
pOH = 13
4. [OH-] = 1 * 10^-14/ 1 x 10-4
[OH-] = 1 * 10^-10
pOH = 10
5. pOH = -log( 1 x 10-7) = 7
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Copper metal has a face-centered cubic structure with all atoms at lattice points and a density of 8.93 g/cm^3. The edge length of the unit cell is 361.5 pm. Calculate the mass of 1 atom of copper.
The mass of 1 atom of copper metal in the given face-centered cubic structure is determined as 1.054 x 10⁻²² g.
Mass of 1 atom of copperThe mass of 1 atom of copper is calculated as follows;
mass of 1 atom of copper = molar mass of copper / Avogadro's number
substitute the value of molar mass of copper and Avogadro's number;
mass of 1 atom of copper = (63.5 g/mol) / (6.023 x 10²³)
mass of 1 atom of copper = 1.054 x 10⁻²² g
Thus, the mass of 1 atom of copper is determined as 1.054 x 10⁻²² g.
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determine the percentage composition by mass of each of the elements in the following compounds
a. calcium chloride, cacl2
Answer:
63.9%
Explanation:
moral mass of x (# x ions) -divided by- Moral mass of compound.
% of cl = (35.5g) (2 cl ions) -divided by- 111.1g × 100
%= 63.9%
15) The average human is ~60% water, which translates to ~44.3 kg of water. If you eat a Reece's peanut butter cup (105 Calories or 4.39 x 105J), how many degrees Celsius (°C) should the 44.3kg of water rise. The specific heat of water is 4.184 J/g.°C. A) 2.37 x 103°C B) 5.66 x 104°C C) 41.5°C D) 2.37°C E) 0.566°C 4.39x1055 0.043 y 4.18488.0
Answer: D) 2.37°C
Explanation:
[tex]4.39x10^5J(\frac{g°C}{4.184J} )(\frac{kg}{1000g})(\frac{1}{44.3kg} )[/tex] [tex]=2.37°C[/tex]
A buffer is prepared by adding 150mL of 0.50 M NH3 to 250mL of 0.50 M NH4NO3. What is the pH of the final solution? (Kb for NH3 = 1.8 x 10^-5)
From the calculations, the pH of the final solution is 9.04.
What is the pH of the buffer?We can use the Henderson Hasselbach equation to obtain the final pH of the solution in terms of the pKb and the base concentration.
Number of moles of salt = 250/1000 L * 0.5 M = 0.125 moles
Number of moles of base = 150/1000 L * 0.5 M = 0.075 moles
Total volume of solution = 250ml + 150ml = 400ml or 0.4 L
Molarity of base = 0.075 moles/ 0.4 L = 0.1875 M
Molarity of salt = 0.125 moles/ 0.4 L = 0.3125 M
pOH = pKb + log[salt/base]
pKb = -log(1.8 x 10^-5) = 4.74
pOH = 4.74 + log[0.3125/0.1875 ]
pOH = 4.96
pH = 14- 4.96
pH = 9.04
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Abc Which excerpt from an essay about higher education most clearly shows an example of logos? According to recent studies, more women than ever are attending four-year colleges. In fact, 36.6 percent of women attended college in 2019, compared to 35.4 percent of men. O When I went to college in 1994, I was the first person in my family to do so. My mother stood in my dorm room, surrounded by boxes of clothes and trinkets and holding back tears. O I was in awe of my sociology professor, who had studied the historical impacts of food in African American culture for 10 years. She spoke with such passion and energy that it was difficult to take your eyes off her. O Many college students look to land an exciting internship, believing that it will open doors in their field of study. However, internships can often distract from schoolwork. Mark this and return Save and Exit Next Submit
The excerpt from an essay about higher education that most clearly shows an example of logos is:
Option d: Many college students look to land an exciting internship, believing that it will open doors in their field of study. However, internships can often distract from schoolwork.What is Logos?The Logos Definition is one that is often argued by a lot of people as people tends to appeal to others emotions and some other times, people do appeal to one's' ethics or morals.
The term logos is a term that connote the use of logic. It also includes the use of deductive reasoning to get to a conclusion.
The excerpt from an essay about higher education that most clearly shows an example of logos is:
Option d: Many college students look to land an exciting internship, believing that it will open doors in their field of study. However, internships can often distract from schoolwork.Option d is correct because it shows the cause and its effect.
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A 1.00-mole sample of dry ice (solid CO₂) is placed in a flexible, sealed container and allowed to sublime. After complete sublimation, what will be the
container volume, in liters, at 26°C and 0.983 atm pressure?
Container volume, 26°C, and 0.983 atm pressure is =24.9 liters.
What is a Moles?A mole is defined as the quantity of a material that includes precisely 6.02214076 X 1023 of the substance's elementary entities.A substance is said to have a mole with a mass equal to 12.000 g of 12C and the same number of basic units as atoms.The mole can be used to calculate the quantities involved in chemical processes and identify the simplest formula of a compound. The molarity notion, which is related, helps discuss reactions in solutions. The number of moles of a solute in a liter of solution is known as molarity (M).Quantities that cannot be quantified using units like grams or milligrams are referred to as moles. A mole thus counts the quantity of atoms, ions, or molecules.Container volume, in liters, at 26°C and 0.983 atm pressure:
Given=1.00
V=?
PV=nRT
T=26°C+273.15
=299.15K
R=0.08201Lamt/k
P=0.983atm
V=nRT/p
[tex]V=\frac{1.00 mole(0.08201Lamt/k)299.15K}{0.983atm}[/tex]
V=24.9 liters
Container volume, 26°C, and 0.983 atm pressure is =24.9 liters.
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The Volume in the container is 25L .
What is Ideal Gas?
Ideal gas is hypothetical gas whose molecules occupy negligible space and have no interaction, and which consequently obeys the gas laws exactly.
We have given
Pressure=0.983atm
moles=16
Temperature= 26°C
T →273+26=299K
Volume = ?
PV = nRT
V= 1×0.0821×299/0.983
By solving this equation we get
V= 24.9L≈25L
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Explain why the middle portion of ship shows more rust than either the top most or the bottom most part
Answer:
A ship comprises of both visible as well as invisible parts. . The most forward part of a ship is called a Bow, the left-hand side of . at a topmost accessible height of the ship and just above the bridge . The mast is a rangy spar arrangement which is elevated more or less vertically to the Centre line of a ship .
Which sample contains the largest number of oxygen atoms? Select one: a. 8.0 g of carbon dioxide b. 8.0 g of potassium chlorate c. 8.0 g of calcium perchlorate d. 8.0 g of sodium hydroxide
The sample with the largest number of oxygen atoms will be calcium perchlorate.
Number of atoms in a compoundSince we are not looking at the number of moles, the mass of the compounds has no bearing on the number of atoms of oxygen.
The chemical formula for carbon dioxide is [tex]CO_2[/tex]. Thus, it has 2 atoms of oxygen.The chemical formula for potassium chlorate is [tex]KClO_3[/tex]. Thus, it has 3 oxygen atoms.The chemical formula for calcium perchlorate is [tex]Ca(ClO_4)_2[/tex]. Thus, it has 8 atoms of oxygen.The chemical formula for sodium hydroxide is NaOH. Thus, it has 1 atom of oxygen.Therefore, the compound with the largest number of oxygen atoms is calcium perchlorate.
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A student measures the length of an object to be 152 cm. What is the measurement in km?
Answer: 0.00152 km
Explanation:
(A) O ( B) La (C) Rb (D) Mg (E) N
1. What is the most electronegative element of the above?
2. Which element exhibits the greatest number of different oxidation states?
3. Which of the elements above has the smallest ionic radius for its most commonly found ion?
1. The most electronegative element is O (a)
2. The element that exhibits Greatest number of oxidation states is N (e)
3. The Smallest ionic radius for its most common ion is found for Mg (d)
1. Electronegativity is tendency of an atom to attract shared pair of electrons. Across a period, it increases from left to right while in a group, it decreases as we move down. The most electronegative elements are found in the top right of the periodic table because of the increase in effective nuclear charges. Hence, O is most electronegative element.
2. Oxidation state is the total number of electrons that an atom can either gain or loss to form a chemical bond. N exhibits a wide range of oxidation states from -3 to +5 because of half filled p orbital which is more stable.
3. Ionic radius is the radius of a monatomic ion in an ionic crystal structure. [tex]Mg^{2+}[/tex] has higher number of protons that will attract the negatively charged valence electrons to a greater extent hence shortening the distance.
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the proper answer gets marked brainiest, answer what the question is asking.
What classifies a substance as an element?
What classifies a substance as a compound?
Actually, answer what the question is asking and give a short answer. No copying and pasting.
A substance is an element if it consists of a single type of atom. A substance is a compound if it is made up of more than one element.
Elements and compoundsIn chemistry, an element is defined as all pure substances consisting of the same atom. For example, magnesium and potassium metal are all elements because they consist of magnesium and potassium atoms only.
On the other hand, compounds are defined as substances consisting of 2 or more atoms of different elements. For example, sodium chloride consists of atoms of sodium and chlorine. Hence, it is considered to be a compound.
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Consider the balanced equation:
Mg2Si (s) + 2 H2O (l) ---> 2 Mg(OH)2 (aq) + SiH4 (g)
Calculate the grams of silane gas, SiH4, formed when 8.48 g of Mg2Si react with excess H2O.
2. Consider the balanced equation:
4 NH3 (g) + 7 O2 (g) ---> 4 NO2 (g) + 6 H2O (g)
What is the mass of H2O produced when 109.4 g of NH3 is completely reacted
1. The mass of silane gas, SiH₄ formed from the reaction is 3.57 g
2. The mass of H₂O produced from the reaction is 173.75 g
1. How to determine the mass of SiH₄ formedBalanced equation
Mg₂Si (s) + 4H₂O (l) ---> 2Mg(OH)₂ (aq) + SiH₄ (g)
Molar mass of Mg₂Si = (24×2) + 28 = 76 g/mol
Mass of Mg₂Si from the balanced equation = 1 × 76 = 76 g
Molar mass of SiH₄ = 28 + (4×1) = 32 g/mol
Mass of SiH₄ from the balanced equation = 1 × 32 = 32 g
SUMMARY
From the balanced equation above,
76 g of Mg₂Si reacted to produce 32 g of SiH₄
From the above information, we can obtain the mass of SiH₄ produced by the reaction of 8.48 g of Mg₂Si as illustrated below:
From the balanced equation above,
76 g of Mg₂Si reacted to produce 32 g of SiH₄
Therefore,
8.48 g of Mg₂Si will react to produce = (8.48 × 32) / 76 = 3.57 g of SiH₄
Thus, 3.57 g of SiH₄ were obtained from the reaction.
2. how to determine the mass of H₂O producedBalanced equation
4NH₃ (g) + 7O₂ (g) ---> 4NO₂ (g) + 6H₂O (g)
Molar mass of NH₃ = 14 + (1×3) = 17 g/mol
Mass of NH₄ from the balanced equation = 4 × 17 = 68 g
Molar mass of H₂O = (2×1) + 16 = 18 g/mol
Mass of H₂O from the balanced equation = 6 × 18 = 108 g
SUMMARY
From the balanced equation above,
68 g of NH₃ reacted to produce 108 g of H₂O
From the above information, we can obtain the mass of H₂O produced by the reaction of 109.4 g of NH₃ as illustrated below:
From the balanced equation above,
68 g of NH₃reacted to produce 108 g of H₂O
Therefore,
109.4 g of NH₃ will react to produce = (109.4 × 108) / 68 = 173.75 g of H₂O
Thus, 173.75 g of H₂O were obtained from the reaction.
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QUESTION 3
List the two ways of determining the chloride content of water
After removing the particles, the solution's chloride content can be assessed using various techniques, such as titration and photometry.
What is the importance of chloride determination?One of the most prevalent inorganic anions in water and wastewater is chloride, which forms the chloride (Cl-) ion. Sodium chloride, a specific food item that passes through the digestive tract undigested, has a higher chloride concentration in wastewater than in raw water. Due to salt water leaking into the sewage system, coast chloride may be present in high concentrations along the sea. Additionally, industrial processes may cause it to rise.The salty taste caused by chloride concentration in drinkable water varies and depends on the water's chemical makeup. If sodium cation is present, some waters with 250 mg/L Cl- may have a flavor that can be identified as salty. On the other hand, when calcium and magnesium cations predominate, the typical salty taste may be missing in fluids containing as much as 1000 mg/L. A high chloride level may injure developing plants, steel pipelines, and structures.The salinity of various water sources can be determined using the detected chloride ions. It is a crucial parameter for brackish water (or seawater or industrial brine solution) because it indicates how much desalting of the apparatus is needed. Additionally, it affects the COD calculation, necessitating a modification based on the amount present or adding a complexing agent like HgSO4. Additionally, column studies that predict the fate of various pollutants in soil and liquid media use chloride ions as tracer ions.After removing the particles, the solution's chloride content can be assessed using various techniques, such as titration and photometry.
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Do the following statement describe physical or chemical property.
Uranium is a radioactive element
The fact that uranium is a radioactive element is a chemical property. Details about radioactivity can be found below.
What is radioactivity?Radioactivity is the spontaneous emission of ionizing radiation as a result of a nuclear reaction.
Radioactivity, which is the emission of particles from an unstable nucleus, is a chemical property.
Therefore, it can be said that the fact that uranium is a radioactive element is a chemical property.
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Gelatin is a solid that can strengthen protein networks. How would yogurt that contains gelatin be different from yogurt that does not contain gelatin? Explain your answer.
Ice cream that contains gelatin will have a thicker consistency than on that does not contain gelatin.
What is gelatin?Gelatin is a proteoglycan which is made from boiling tendons.
Gelatin is used as a thickening agent.
Therefore Ice cream that contains gelatin will have a thicker consistency than on that does not contain gelatin.
In conclusion, gelatin is used to thicken foods.
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If I have 4.5 liters of gas at a temperature of 33 0C and a pressure of 6.54 atm, what will be the pressure of the gas if I raise the temperature to 94 0C and decrease the volume to 2.3 liters?
This is an exercise in the general or combined gas law.
To start solving this exercise, we must obtain the following data:
Data:V₁ = 4.5 lT₁ = 33 °C + 273 = 306 kP₁ = 6.54 atmT₂ = 94 °C + 273 = 367 kV₂ = 2.3 lP₂ = ¿?We use the following formula:
P₁V₁T₂ = P₂V₂T₁ ⇒ General FormulaWhere
P₁ = Initial pressureV₁ = Initial volumeT₂ = Initial temperatureP₂ = Final pressureV₂ = Final volumeT₁ = Initial temperatureWe clear the general formula for the final pressure.
[tex]\large\displaystyle\text{$\begin{gathered}\sf P_{2}=\frac{P_{1}V_{1}T_{2} }{V_{2}T_{1}} \ \to \ Clear \ formula \end{gathered}$}[/tex]
We solve by substituting our data in the formula:
[tex]\large\displaystyle\text{$\begin{gathered}\sf P_{2}=\frac{(6.54 \ atm)(4.5 \not{l})(367 \not{K}) }{(2.3 \not{l})(306 \not{k})} \end{gathered}$}[/tex]
[tex]\large\displaystyle\text{$\begin{gathered}\sf P_{2}=\frac{10800.81}{ 703.8 } \ atm \end{gathered}$}[/tex]
[tex]\boxed{\large\displaystyle\text{$\begin{gathered}\sf P_{2}=15.346 \ atm \end{gathered}$} }[/tex]
If I raise the temperature to 94°C and decrease the volume to 2.3 liters, the pressure of the gas will be 15,346 atm.
Answer:
15.35 atm
Explanation:
Combined Gas Law
[tex]\sf \dfrac{P_1V_1}{T_1}=\dfrac{P_2V_2}{T_2}[/tex]
Temperature must be in kelvins (K).
To convert Celsius to kelvins, add 273.15.
Volume can be in any unit.
Given values:
P₁ = 6.54 atmV₁ = 4.5 LT₁ = 33 °C = 33 + 273.15 = 306.15 KP₂ = V₂ = 2.3 LT₂ = 94 °C = 94 + 273.15 = 367.15 KRearrange the equation to isolate P₂:
[tex]\sf \implies P_2=\dfrac{P_1V_1T_2}{V_2T_1}[/tex]
Substitute the given values into the equation:
[tex]\sf \implies P_2=\dfrac{6.54 \cdot 4.5 \cdot 367.15}{2.3 \cdot 306.15}[/tex]
[tex]\sf \implies P_2=15.34516967[/tex]
Therefore, the pressure of the gas will be 15.35 atm (2 d.p.).
Research the ecology of your region and find one species that is endangered. Find an estimate of the population of the species in your region. Describe the threats facing that species, especially threats posed by human activities.
The endangered species in my region with their estimate population are:
Northwestern African Cheetah - 250 West African Lion - 400 What threat faces Northwestern African Cheetah?This cheetah is said to be an endangered species because of their loss of their habitat and also due to fragmentation, trade and little human-activities.
West African Lion is said to be an endangered species because the lion's historic range in West Africa was said to be lowered by a lot of amount or scale as a result of land use changes and human activities such as falling of trees, buildings, etc.
Hence the endangered species in my region with their estimate population are:
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PLEASE HELP!!!
A sample of nitrogen at 20.0 °C has a volume of 588 mL at a pressure of 924 mmHg. To change the volume to 1008 mL, what must be the new pressure?
Answer:
539 mmHg
Explanation:
Using Boyle's Law,
(588)(924)=(1008)(pressure)
So, the pressure is 539 mmHg.
In a calorimetry experiment 2.50 g of methane is burnt in excess oxygen. 30% of the energy released during the combustion is absorbed by 500 g of water, the temperature of which rises from 25°C to 68°C. The specific heat capacity of water is 4.184 J/g°C. What is the total energy released per gram of methane burnt?
The total energy released per gram of methane burnt is 119,941.3 J/g.
Energy absorbed by waterQ = mcΔθ
where;
m is mass of waterc is specific heat of waterΔθ is change in temperatureQ = (500)(4.184)(68 - 25)
Q = 89,956 J
Total energy released per gram of methane burnt0.3T = 89,956 J
T = 89,956 J/0.3
T = 299,853.3 J
Total energy per gram of methane, E = T.E/m
E = (299,853.3 J) / (2.5 g)
E = 119,941.3 J/g
Thus, the total energy released per gram of methane burnt is 119,941.3 J/g.
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How are microfauna measured?
In centimeters
In millimeters
In nanometers
Any of the above
Microfauna are measured in all of the above units and is denoted as option D.
What is Microfauna?These are referred to as microscopic animals which lack mitochondrion and exists in the soil etc. The nematodes and protozoa are mostly common organisms among them.
Microfauna can be seen with the use of microscope and can be measured in centimeters, millimeters etc based on the size of their body structure.
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which gas law is not included in the combined gas law
Answer:
Watson law is not part of the combined gas law
There are 5 basic gas laws of ideal gases:
Boyle's Law: volume (V) is inversely proportional to pressure (P)Charles' Law: V is proportional to temperature (T)Gay-Lussac's Law: P is proportional to TDalton's Law: The total pressure exerted by a mixture of ideal gases is equal to the sum of the pressures of the individual gasesAvogadro's Law: All equal volumes of ideal gases contain the same number of gas particles (at constant T and P); V is proportional to moles (n)The Combined Gas LawThis law features Charles', Boyle's and Gay-Lussac's laws.
Therefore, Dalton's and Avogadro's laws are exluded.
Determine the empirical formula of a compound containing 40.6 grams of carbon, 5.1 grams of hydrogen, and 54.2 grams of oxygen.
In an experiment, the molar mass of the compound was determined to be 118.084 g/mol. What is the molecular formula of the compound?
For both questions, show your work or explain how you determined the formulas by giving specific values used in calculations.
The Empirical formula of compound is C₁H₂O₁. The Molecular Formula of the compound is 4 (C₁H₂O₁).
What is Empirical Formula ?Empirical formula is the simplest whole number ratio of atoms present in given compound.
Element % Atomic mass Relative no. of atoms Simplest whole ratio
C 40.6 12 [tex]\frac{40.6}{12}[/tex] = 3.3 [tex]\frac{3.3}{3.3} = 1[/tex]
H 5.1 1 [tex]\frac{5.1}{1}[/tex] = 5.1 [tex]\frac{5.1}{3.1} = 2[/tex]
O 54.2 16 [tex]\frac{54.2}{16}[/tex] = 3.3 [tex]\frac{3.3}{3.3} = 1[/tex]
The Empirical formula of compound is C₁H₂O₁ or CH₂O
How to find the Molecular formula of compound ?Molecular formula = Empirical formula × n
[tex]n = \frac{\text{Molecular weight}}{\text{Empirical Formula weight}}[/tex]
[tex]= \frac{118.084}{30}[/tex]
= 4
Molecular formula = n × Empirical formula
= 4 (C₁H₂O₁)
Thus from the above conclusion we can say that The Empirical formula of compound is C₁H₂O₁. The Molecular Formula of the compound is 4 (C₁H₂O₁).
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Positive ions usually form from ____
and are called cations.
Metals
Noble gases
Nonmetals
Answer:
Metals
Explanation:
Positive ions are formed when atoms give up some valence electrons in order to have a full octet. The atoms most likely to do this have a small number of valence electrons. Most to these atoms are generally in the s-block (left side) of the periodic table. These elements are metals.
*nonmetals are located in the p-block (right side) and noble gases are located in the 18th column (far right column)
What is oxidized in the reaction below?
H₂ + Cl₂
2HCI
Answer:
Dihydrogen
Explanation:
Dihydrogen is FORMALLY oxidized.... i.e. its oxidation number increases... And we adds the half equations together such that the electrons are eliminated
Volume is: A. Non of these. B. How much matter something contains.
What is the mole fraction of sulfuric acid in a solution made by adding 34 g of sulfuric acid (H2SO4 = 98 g/mol) to 100 g of water (H2O = 18 g/mol)?
Answer:
Mole Fraction = 0.059
Explanation:
To find the mole fraction, you need to (1) convert grams H₂SO₄ and H₂O to moles (via molar mass) and then (2) calculate the mole fraction.
(Step 1)
Molar Mass (H₂SO₄): 98 g/mol
34 grams H₂SO₄ 1 mole
-------------------------- x ------------------- = 0.347 moles H₂SO₄
98 grams
Molar Mass (H₂O): 18 g/mol
100 grams H₂O 1 mole
------------------------- x -------------------- = 5.56 moles H₂O
18 grams
(Step 2)
moles solute
Mole Fraction = -------------------------------------------------
moles solute + moles solvent
0.347 moles H₂SO₄
Mole Fraction = -----------------------------------------------------------
0.347 moles H₂SO₄ + 5.56 moles H₂O
Mole Fraction = 0.059
The cell membrane is
a)semi permeable
b)selectively permeable
Answer:
A. Semi Permeable.
Explanation:
Cell membranes are semi permeable.
What is the numerical value for Q for this reaction? Remember to always express your answer to correct number of significant figures.
The reaction is not at equilibrium because Q >P hence the reaction moves towards the left hand side.
What is the equilibrium constant?The equilibrium constant is a figure that tells us the extent to which the reactants have been converted to products in a reaction.
Now we have the reaction; PCl3(g) + Cl2(g) ⇄ PCl5(g) hence we can write;
Q = [PCl5]/[PCl3] [Cl2]
Q = 0.39/0.21 * 0.41
Q = 4.5
The reaction is not at equilibrium because Q >P hence the reaction moves towards the left hand side.
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a saline solution begins to freeze at -1.13 degrees. Express the concentration of NaCl in this solution in mass%. Kf for water is 1.86C degree/m.
The Percentage mass of NaCl is 1.78%.
What is the percent mass concentration of the NaCl in saline solution.The percent mass concentration of NaCl in the saline solution is determined from the molality of the solution.
The molality of the solution is further obtained from the freezing point depression formula.
The freezing point depression formula is given as follows:
ΔT = Kf * m * iwhere;
ΔT is the freezing point changeKf is a constantm is the molality of the solutioni is the van't Hoff factorFor the solution of NaCl;
ΔT = 0 - (-1.13) = 1.13
Kf = 1.86 °/m
i = 2
m = ΔT/(Kf * i)
m = 1.13/(1.86 * 2)
m = 0.3038 mol/kg
molar mass of NaCl = 58.5 g/mol
Mass of NaCl = 0.3038 * 58.5 = 17.8 g in
Percentage mass of NaCl = (17.8/1000) * 100
Percentage mass of NaCl = 1.78%
In conclusion, the percent mass of NaCl is obtained from the molality of the solution.
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