Answer: The [tex]K_{sp}[/tex] value for calcium hydroxide at this temperature is [tex]1.08 \times 10^{-4}[/tex].
Explanation:
Given: Mass of [tex]Ca(OH)_{2}[/tex] = 0.225 g
Volume = 0.100 L
As moles is the mass of substance divided by its molar mass.
So, moles of [tex]Ca(OH)_{2}[/tex] (molar mass = 74 g/mol) is calculated as follows.
[tex]Moles = \frac{mass}{molar mass}\\= \frac{0.225 g}{74 g/mol}\\= 0.003 mol[/tex]
Molarity is the number of moles of substance present in a liter of solution.
Hence, molarity of given solution will be as follows.
[tex]Molarity = \frac{moles}{Volume (in L)}\\= \frac{0.003 mol}{0.1 L}\\= 0.03 M[/tex]
The equation for dissociation of [tex]Ca(OH)_{2}[/tex] is as follows.
[tex]Ca(OH)_{2} \rightarrow Ca^{2+} + 2OH^{-}[/tex]
This means that [tex][Ca^{2+}] = 0.03[/tex] and [tex][OH^{-}] = 2 \times 0.03 = 0.06[/tex]. Hence, [tex]K_{sp}[/tex] value for this reaction is calculated as follows.
[tex]K_{sp} = [Ca^{2+}][OH^{-}]^{2}\\= (0.03) \times (0.06)^{2}\\= 1.08 \times 10^{-4}[/tex]
Thus, we can conclude that the [tex]K_{sp}[/tex] value for calcium hydroxide at this temperature is [tex]1.08 \times 10^{-4}[/tex].
What volume of chlorine gas at 27 °C, 812 mmHg, is required to react with an excess of carbon disulfide so that 5.00kJ of heat is evolved?
Answer:
The correct answer is 1.21 L.
Explanation:
Based on the given information, the reaction will be,
CS2 (l) + 3Cl2 (g) ⇒ CCl4 (l) + S2Cl2 (l)
By using the standard values of the substances, the standard enthalpy of the reaction is,
ΔH° = [(-139.5) + (-58.5) – 0 – (87.3)] kJ/mol
= -285.3 kJ/mol
The amount of heat evolved for 3 moles of chlorine reacted us 285.3 kJ.
Now the number of moles of chlorine needed to react to produce 5.00 kJ is,
= 5.00 kJ × 3 mol Cl2/285.3 kJ
= 0.0526 mol Cl2
Now the volume of chlorine gas at 27degree C and 812 mmHg will be,
Volume = 0.0526 mol Cl2 × 0.0821 Latm/mol K × 300 K/ 1.07 atm
= 1.21 L
What type of intermolecular forces are due to
the attraction between temporary dipoles
and their induced temporary dipoles?
Select one:
a. London dispersion
b. Metallic bond
C. Covalent bond
d. Hydrogen bond
e. lonic bond
Answer:
A. London dispersion
Explanation:
London dispersion force is a temporary attractive force that results when the electrons in two adjacent atoms occupy positions that make the atoms form temporary dipoles.
The intermolecular forces are due to the attraction between temporary dipoles, and their induced temporary dipoles are the type of London dispersion force. Therefore, option A is correct.
What is london dispersion force ?When the electrons in two nearby atoms occupy positions that cause the atoms to temporarily form dipoles, the consequence is the London dispersion force, a transient attractive force. The term "induced dipole-induced dipole attraction" is frequently used to describe this effect.
The electron density of a molecule is redistributed towards another molecule because the electrons in nearby molecules "flee" when they repel one another. This is typically explained as the instantaneous production of attracted dipoles.
The material's atomic or molecular weight affects the London dispersion forces. More electrons and stronger London forces are present in heavier atoms or molecules. They are therefore more difficult to melt or boil.
Thus, option A is correct.
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Science- I need help with a question really quick I’m ending school soon
Los catalizadores sirven para detener una reacción química ?
Answer:
si
Explanation:
Los catalizadores son sustancias que aceleran una reacción química, proporcionando una ruta alternativa para romper y formar nuevos enlaces entre átomos. Su importancia reside en el hecho de que este nuevo camino requiere menos energía que el original, lo que facilita el proceso.
A mixture of 0.224 g of H2, 1.06 g of N2, and 0.834 g of Ar is stored in a closed container at STP. Find the volume (in L) of the container, assuming that the gases exhibit ideal behavior.
Answer: The volume of given container is 3.83 L.
Explanation:
Given: Mass of [tex]H_{2}[/tex] = 0.224 g
Mass of [tex]N_{2}[/tex] = 1.06 g
Mass of Ar = 0.834 g
Since, moles is the mass of a substance divided by its molar mass. Therefore, moles of given substances present in the mixture are as follows.
Moles of [tex]H_{2}[/tex] are:
[tex]Moles = \frac{mass}{molar mass}\\= \frac{0.224 g}{2 g/mol}\\= 0.112 mol[/tex]
Moles of [tex]N_{2}[/tex] are:
[tex]Moles = \frac{mass}{molar mass}\\= \frac{1.06 g}{28 g/mol}\\= 0.038 mol[/tex]
Moles of Ar are:
[tex]Moles = \frac{mass}{molar mass}\\= \frac{0.834 g}{40 g/mol}\\= 0.021 mol[/tex]
Total moles = (0.112 + 0.038 + 0.021) mol = 0.171 mol
Now, using ideal gas equation the volume is calculated as follows.
PV = nRT
where,
P = pressure
V = volume
n = no. of moles
R = gas constant = 0.0821 L atm/mol K
T = temperature
Substitute the values into above formula as follows.
[tex]V = \frac{nRT}{P}\\= \frac{0.171 mol \times 0.0821 L atm/mol K \times 273 K}{1 atm}\\= 3.83 L[/tex]
Thus, we can conclude that the volume of given container is 3.83 L.
If 143.56 mL of 0.6653 M ammonium carbonate reacts with 175.37 mL of 0.8732 M chromium(III) sulfate in a double replacement reaction and produces 7.543 g of chromium(III) carbonate, what is the percent yield of the reaction
Write a conclusion statement that addresses the following questions: • Explain what the color change indicated about the changes in the concentrations of Co(H2O)62+ and CoCl42– in each trial. • Do your data support or fail to support your hypothesis (include examples)? • How do you think the investigation can be explored further?
When the concentration of the HCl is varied, the color of the solution is changed as the equilibrium position moves to the left or right.
What is equilibrium?The term equilibrium in a chemical reaction connotes that the forward and the revers reactions proceed at the same rate. Let us note that Co(H2O)6^2+ is pink in color while CoCl4^2– is blue in color.
As such, when the concentration of the HCl is varied, the color of the solution is changed as the equilibrium position moves to the left or right.
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In this lab you will need to prepare solutions using dilutions. Starting with the stock 0.300 M NaOH solution, how would you prepare a 0.100 M NaOH solution (using 0.300 M NaCl as the diluent)
Answer:
1/3 dilution : 1 volume of stock solution + 2 volumes of diluent
Explanation:
Concentrated solution = 0.300 NaOH
Diluted solution = 0.100 NaOH
The dilution factor is : 0.100/0.300 = 1/3
Thus, we have to dilute three times the stock solution. For this, we take 1 volume of stock solution and then we add 2 volumes of diluent. As result, we will have 1 volume of stock solution in a total of 3 volumes. For example, we take 1 mL of 0.300 NaOH and then we add 2 mL of diluent (0.300 NaCl). The final concentration after dilution will be:
Cd = 0.300 M x 1 mL/3 mL = 0.100 M
(1.21 x 10^-3 + 1.3 x 10^-3) x 6.453 x 10^2 =
Answer:
1.61
Explanation:
If an aqueous solution of ___________ is added to a mixture of barium nitrate and silver nitrate, the barium ion will precipitate, but the silver ion would remain in solution.
Answer:
sodium fluoride
Explanation:
When we add sodium fluoride to a solution of a given mixture, we get barium fluoride from Ba, which would be an insoluble salt, and silver fluoride from Ag, which would be a soluble salt.
The solubility rule will be used to determine the barium salt that forms as a precipitate and leaves Ag+ salt in the solution.
From the following equations, we will see that the precipitate is formed in Ba but Ag remains dissolved in the solution.
[tex]Ba(NO_3)_2{(aq)} + 2NaF_{(aq)} \to BaF_{2(s)} +2NaNo_{3(aq)}[/tex]
[tex]AgNo_{3(aq)} +NaF_{(aq)} \to AgF_{(aq)} + NaNO_{(aq)}[/tex]
What is baking soda chemically known as ? Excessive use of chemical
fertilizer is not good. Justify.
Answer:
Baking Soda is NaHCO3 ---Sodium hydrogen Carbonate
Excessive use of Fertilizer can cause plants to develop shallow root systems,Decrease soil fertility and reduce Quality of Crops.
Answer:
Sodium bicarbonate, also called sodium hydrogen carbonate, or bicarbonate of soda, is a source of carbon dioxide and so is used as an ingredient in baking powders, in effervescent salts and beverages, and as the main constituent of dry-chemical fire extinguishers.
Explanation:
Which of the following statements is FALSE. Select one: A. Two of the statements are false. B. In the synthesis of aspirin, the main impurities are salicylic acid and acetic acid. C. Aspirin was purified in the lab by recrystallizing the crude aspirin. The melting point of the purified aspirin is expected to be lower than the melting point of crude aspirin. D. In the analysis of aspirin, the greater the amount of salicylic acid impurity in the aspirin, the smaller the amount of NaOH needed for the hydrolysis of aspirin. E. If the crude aspirin is not entirely pure, the temperature range at which it melts will be larger than pure aspirin.
Answer:
Aspirin was purified in the lab by recrystallizing the crude aspirin. The melting point of the purified aspirin is expected to be lower than the melting point of crude aspirin.
Explanation:
The presence of impurities in a sample lowers the melting point of the impure substance. Hence the melting point of an impure substance is always less than the melting point of the corresponding pure substance.
Bearing this in mind, the statement "Aspirin was purified in the lab by recrystallizing the crude aspirin. The melting point of the purified aspirin is expected to be lower than the melting point of crude aspirin." is found to be false since impure substances tend to have a slightly lower melting point than the pure substance, and a broader melting temperature range.
To which family of organic compounds does CH3COCH2CH2CH3 belong?
Answer:
I think:
CH3COCH2CH2CH3 belongs to ketone because it has a carbonyl group C=O in its structure.
Acids and bases are chemical molecules with very different characteristics.
a. True
b. Fasle
Answer:
TRUE ,hope it helped you
Explanation:
Which of these half-reactions represents reduction?
I. Fe2+ → Fe3+
II. Cr2O72- → Cr3+
III. MnO4- → Mn2+
Answer: The half-reactions represents reduction are as follows.
[tex]Cr_{2}O^{2-}_{7} \rightarrow Cr^{3+}[/tex][tex]MnO^{-}_{4} \rightarrow Mn^{2+}[/tex]Explanation:
A half-reaction where addition of electrons take place or a reaction where decrease in oxidation state of an element takes place is called reduction-half reaction.
For example, the oxidation state of Cr in [tex]Cr_{2}O^{2-}_{7}[/tex] is +6 which is getting converted into +3, that is, decrease in oxidation state is taking place as follows.
[tex]Cr_{2}O^{2-}_{7} + 3 e^{-} \rightarrow Cr^{3+}[/tex]
Similarly, oxidation state of Mn in [tex]MnO^{-}_{4}[/tex] is +7 which is getting converted into +2, that is, decrease in oxidation state is taking place as follows.
[tex]MnO^{2-}_{4} + 5 e^{-} \rightarrow Mn^{2+}[/tex]
Thus, we can conclude that half-reactions represents reduction are as follows.
[tex]Cr_{2}O^{2-}_{7} \rightarrow Cr^{3+}[/tex][tex]MnO^{-}_{4} \rightarrow Mn^{2+}[/tex]What is the molarity and normality of solution containing 80 g of NaOH dissolved in 2.0 liter of the solution?
AAnswer:
Explanation:
Which is considered a good insulator of heat? *
1 point
Captionless Image
A. aluminum, because it allows heat to flow easily.
B. glass, because it allows heat to flow easily.
C. plastic, because heat is unable to flow easily through it.
Answer: Aluminum, because it allows heat to flow easily.
Have a nice day!
4- 4110 kg of R-134a at 300 kPa fills a rigid container whose volume is 14 L. Determine the temperature and total enthalpy in the container. The container is now heated until the pressure is 600 kPa. Determine the temperature and total enthalpy when the heating is completed.
The correct question is: 10 kg of R-134a at 300 kPa fills a rigid container whose volume is 14 L. Determine the temperature and total enthalpy in the container. The container is now heated until the pressure is 600 kPa. Determine the temperature and total enthalpy when the heating is completed.
Answer: The temperature is [tex]21.6^{o}C[/tex] and total enthalpy when the heating is completed is 300 kJ.
Explanation:
Given: Mass = 10 kg
Volume = 14 L
Final pressure = 600 K
First, convert volume from L to [tex]m^{3}/kg[/tex] as follows.
[tex]v_{1} = \frac{14 \times 10^{-3}}{10}\\= 0.0014 m^{3}/kg[/tex]
According to the R-134a tables at 300 kPa and [tex]0.0014 m^{3}/kg[/tex].
[tex]h_{1}[/tex] = 54.6 kJ/kg
[tex]T_{sat}[/tex] = 0.7 C
[tex]u_{1}[/tex] = 54.1 kJ/kg
Now, at the state 2 [tex]p_{2}[/tex] = 600 kPa and [tex]v_{2} = v_{1} = 0.0014 m^{3}/kg[/tex]
This means that the final temperature at state 2 is [tex]T_{2} = T_{sat} = 21.6^{o}C[/tex]
Hence, the change in enthalpy is calculated as follows.
[tex]\Delta H = m(h_{2} - h_{1})\\= 10(84.6 - 54.6)\\= 300 kJ[/tex]
The first law is applied to transfer the heat transfer as follows.
[tex]Q = m(u_{2} - u_{1})\\= 10(83.8 - 54.1) kJ\\= 297 kJ[/tex]
Thus, we can conclude that the temperature is [tex]21.6^{o}C[/tex] and total enthalpy when the heating is completed is 300 kJ.
Calculate the mass of sucrose needed to prepare a 2000 grams of 2.5% sucrose solution.
Explanation:
[tex] = 2.5\% \times 2000 \\ = \frac{2.5}{100} \times 2000 \\ = 50 \: g[/tex]
if irons temperature goes from 50c to 75c in a 20g sample, how many joules of heat were used?
A. 460
B. 690
C. 75,000
D. 230
E. 34,500
Please help I’ll mark Brainlyist!
Answer:
Option D. 230 J
Explanation:
We'll begin by calculating the temperature change of the iron. This can be obtained as follow:
Initial temperature (T₁) = 50 °C
Final temperature (T₂) = 75 °C
Change in temperature (ΔT) =?
ΔT = T₂ – T₁
ΔT = 75 – 50
ΔT = 25 °C
Thus, the temperature change of the iron is 25 °C.
Finally, we shall determine the amount of heat energy used. This can be obtained as follow:
Mass (M) = 20 g
Change in temperature (ΔT) = 25 °C
Specific heat capacity (C) = 0.46 J/gºC
Heat (Q) =?
Q = MCΔT
Q = 20 × 0.46 × 25
Q = 230 J
Thus, the amount of heat used was 230 J
Question 2
4 pts
Inside a car that was at STP, a 0.95 L bottle warms up to 144 C. If the volume of the bottle
remains constant, what is the pressure, in atm, inside the hot water bottle?
Answer:
1.53 atm
Explanation:
From the question given above, the following data were obtained:
Volume = constant
Initial pressure (P₁) = stp = 1 atm
Initial temperature (T₁) = 273 K
Final temperature (T₂) = 144 °C = 144 °C + 273 = 417 K
Final pressure (P₂) =?
Since the volume is constant, the final pressure can be obtained as follow:
P₁ / T₁ = P₂ / T₂
1 / 273 = P₂ / 417
Cross multiply
273 × P₂ = 417
Divide both side by 273
P₂ = 417 / 273
P₂ = 1.53 atm
Therefore, the final pressure (i.e the pressure inside the hot water bottle) is 1.53 atm.
In a different titration, a 0.7529 g sample of a mixture of solid C6H5COOH and solid NaCl is dissolved in water and titrated with 0.150 M NaOH. The equivalence point is reached when 24.78 mL of the base solution is added. Calculate each of the following.
a. The mass, in grams, of benzoic acid in the solid sample
b. The mass percentage of benzoic acid in the solid sample
Answer:
a. 0.4539g benozic acid
b. 60.29% of benzoic acid in the solid sample
Explanation:
The benzoic acid reacts with NaOH as follows:
C6H5COOH + NaOH → C6H5COONa + H2O
Where 1 mole of the acid reacts per mole of NaOH
The NaCl doesn't react with NaOH
To solve this question we must find the moles of NaOH added = Moles of benzoic acid. With the moles of the acid and its molar mass (C6H5COOH = 122.12g/mol) we can find the mass of the acid and its mass percentage:
a. Moles NaOH = Moles Benzoic acid:
24.78mL = 0.02478L * (0.150mol / L) = 0.003717 moles Benozic acid
Mass benzoic acid:
0.003717 moles Benozic acid * (122.12g / mol) = 0.4539g benozic acid
b. Mass percentage is:
0.4539g / 0.7529g * 100 = 60.29% of benzoic acid in the solid sample
3 A soil has 70% sand, 20% silt
and 10% clay. What kind of soil is it? How do its proportions need
to be changed to make it
into a loam?
Today, as part of the series of posts on soils, we are going to look at ‘soil texture’. Soil forms the basis for all life but it’s important to know about its mineral constitution as well as its biological profile.
Texture refers to the ‘feel’ of the soil. This is affected by the constituent materials found within it, specifically sand, silt and clay particles. A coarse sand will feel gritty but a wet clay will feel heavy and sticky. The texture of a soil has a direct impact on the way the soil reacts to certain environmental conditions – for example, towards drought or heavy rain (with sandy soils more freely draining).
There is a big difference in the size of the different particles.
Coarse sand = diameter 2-0.2mm
Fine sand = diameter 0.2-0.02mm
Silt = diameter 0.02-0.002mm
Clay = diameter less than 0.002mm
Note how the clay particles are much smaller than the sand particles – this is important as it means the total surface area of a clay soil is much greater and so the capacity to hold water is also much greater.
Between the sand, silt and clay particles there are lots of pores. In fact a soil as a whole is generally 45% mineral, 5% organic matter (depending on the soil) and 50% pore space through which air and water can pass.
Sand –
Made up of weathered primary rock minerals.
The particles are irregular in outline.
They are large and so do not pack together easily.
Large pore spaces in between.
Air gets in very easily and water flows rapidly through it.
Silt –
calculate the molecular mass of sodium trioxocarbonate (iv) decahydrate. hints (H= 1, C=12, O=16, Na=23
Given :
A compound sodium trioxocarbonate (iv) decahydrate.
To Find :
The molecular mass of sodium trioxocarbonate (iv) decahydrate.
Solution :
We know, molecular formula of sodium trioxocarbonate (iv) decahydrate is :
Na₂CO₃.10H₂O
Now, we can calculate its molecular mass :
M = ( 2 × 23 ) + 12 + ( 3 × 16 ) + 10 × ( 1 × 2 + 16)
M = 46 + 12 + 48 + ( 10 × 18 )
M = 286 gram/mol
Hence, this is the required solution.
A chemist adds 255 .0 mL of a M copper(II) sulfate solution to a reaction flask. Calculate the mass in grams of copper(II) sulfate the chemist has added to the flask. Round your answer to significant digits.
Answer:
The correct answer is 40.7 grams.
Explanation:
Based on the given information, the volume of copper sulfate added to the solution is 255 ml or 0.255 L. The molarity of copper sulfate is not given, so let us consider it to be 1 M, which can also be written as 1 moles per liter.
The moles of copper sulfate can be determined by using the formula,
Moles = Molarity * Volume in Liters
Moles of CuSO4 = 1 moles/Liter * 0.255 L
Moles of CuSO4 = 0.255 moles
The mass of CuSO4 added in the solution will be,
Mass of CuSO4 = Moles * Molecular mass
= 0.255 moles * 159.609 grams per mole
= 40.7 grams.
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What’s the difference worksheet
Atoms,molecules,elements and compounds
PLEASE PLEASE PLEASE PLEASE PLEASEEEEEEE ANSWER THIS I only have TWO days of school left! And I need this done quickly
Answer:
A molecule is the smallest particle of a substance that is made up of 2 or more atoms
An atom is the smallest particle of any pure element
An element is a substance that cannot be broken chemical and physical processes
A molecule is known as the building block of matter
A compound is a chemical substance that is made up of 2 more more different atoms bonded together
Two airplanes are flying in the sky in such a way that the gravitational attractions between them decreases. The planes must be flying:
A.
away from each other.
B.
next to each other at the same speed.
C.
towards each other.
D.
faster than the speed of sound.
Two airplanes are flying in the sky in such a way that the gravitational attractions between them decreases. The planes must be flying away from each other. Hence option A is correct.
What is gravitational attraction?Gravitational attraction is defined as a basic interaction that pulls everything with mass or energy in the same direction. All objects are subject to gravitational interactions, the strength of which is directly inversely proportional to the product of their masses. The size of an object and the separation between the objects have an impact on gravity.
In order to reduce the gravitational pull, two planes are flying in the sky. There must be a directionality between the aircraft. No matter what is in between the two bodies, there will still be gravitational pull. As a result, even if the medium between the two bodies changed, the gravitational force between them would not.
Thus, two airplanes are flying in the sky in such a way that the gravitational attractions between them decreases. The planes must be flying away from each other. Hence option A is correct.
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Which of the following describes a spectrum?
A. A measurement of the energy associated with an electron
transition
B. A piece of glass that causes light to be divided into different
colors
C. A range of wavelengths or frequencies of electromagnetic
radiation
D. A list of the quantum numbers assigned to a particular electron
Answer: The Answer would be C
Explanation: A spectrum is a Range of Wavelengths and Frequencies of Electromagnetic Radition.
The statement that describe spectrum is a range of wavelengths or frequencies of electromagnetic radiation.
What is Spectrum?Spectrum arrangement or electromagnetic radiations base on their wavelength and frequency which can be visible light, ultraviolet, and infrared light. An instrument that is use for visual observation of spectra is called a spectroscope.
Therefore, The statement that describe spectrum is a range of wavelengths or frequencies of electromagnetic
radiation.
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How many atoms do 24 g of carbon have
1.2 × 10²⁴ atoms C
General Formulas and Concepts:Chemistry
Atomic Structure
Reading a Periodic TableMolesAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Stoichiometry
Using Dimensional AnalysisMath
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to Right Explanation:Step 1: Define
Identify variables
[Given] 24 g C
[Solve] atoms C
Step 2: Identify Conversions
Avogadro's Number
[PT] Molar Mass of C: 12.01 g/mol
Step 3: Convert
[DA] Set up: [tex]\displaystyle 24 \ g \ C(\frac{1 \ mol \ C}{12.01 \ g \ C})(\frac{6.022 \cdot 10^{23} \ atoms \ C}{1 \ mol \ C})[/tex][DA] Divide\Multiply [Cancel out units]: [tex]\displaystyle 1.2034 \cdot 10^{24} \ atoms \ C[/tex]Step 4: Check
Follow sig fig rules and round. We are given 2 sig figs.
1.2034 × 10²⁴ atoms C ≈ 1.2 × 10²⁴ atoms C
Chemical properties of an element are primarily dependent upon Group of answer choices the electron configuration of the element atomic weight of the element the number of main energy levels (electron shells) of the element the number of electrons in the innermost shell of the atom
Answer:
The answer is "the electron configuration of the element".
Explanation:
Electronics are distributed in atomic and molecular orbit via electrons from an atom or a molecule.
It reflects a most frequent dependence on valence electrons in the outer.
Through analyzing the context of the regular periodic table, the individual atoms are helpful. That's also important to understand chemical connections, which hold electrons together. This similar approach helps to explain the specific characteristics of lasers or semiconductors for bulk materials.