The innermost electron shell of an atom can hold up to.
Answers
The innermost electron shell of an atom can hold up to two electrons. This shell is also known as the K shell, and it is closest to the nucleus of the atom. The number of electrons that an atom can hold depends on the electron shell it belongs to.
The first shell (K) can hold up to two electrons, while the second shell (L) can hold up to eight electrons. The third shell (M) can hold up to 18 electrons, and the fourth shell (N) can hold up to 32 electrons. Each electron shell represents a different energy level, with the K shell being the lowest energy level.
Electrons in higher energy levels have more energy and are farther from the nucleus than those in lower energy levels. The outermost electron shell, also known as the valence shell, is the most important in determining an atom's chemical properties since it is the shell involved in chemical bonding.
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Related Questions
what happens when: sulphuric acid reacts with zinc.
Answers
Answer:
hope it helps.
Explanation:
Zinc metal dissolves slowly in dilute sulphuric acid to form solutions containing the aquated Zn(II) ion together with hydrogen gas, H2.
(C)
C21H44 can be cracked to produce ethene.
Cz1H44 — 3C2H4 + C15H32
Relative formula mass (M) of C21H44 = 296
Calculate the mass of C21H44 needed to produce 50.4 kg of ethene.
Answers
Answer:
177.3kg C₂₁H₄₄
Explanation:
Based on the chemical reaction:
C₂₁H₄₄ → 3C₂H₄ + C₁₅H₃₂
Where 1 mole of C₂₁H₄₄ produce 3 moles of ethene, C₂H₄.
To solve this question we need to determine the moles of ethene in 50.4kg. 1/3 these moles are the moles of C₂₁H₄₄ that must be added:
Moles Ethene -Molar mass: 28.05g/mol-
50.4kg = 50400g * (1mol / 28.05g) = 1796.8 moles of ethene
Moles C₂₁H₄₄:
1796.8 moles of ethene * (1 mol C₂₁H₄₄ / 3 mol C₂H₄) = 589.93 moles C₂₁H₄₄
Mass C₂₁H₄₄:
589.93 moles C₂₁H₄₄ * (296g / mol) = 177283g =
177.3kg C₂₁H₄₄2. Which statement about activation energy is true?
Answers
Answer: the statement issues are addressed by the people working together is true about activation.
Explanation:
What are the three states of water and how does each state relate to the levels of energy of the water molecules?
Answers
The three state of matter are solid, liquid and gas. Water exists in all these states as ice, liquid water, water vapor respectively. The level of energy will varies from each state where, gaseous particles possess highest energy.
What is states of matter?Every substances are able to exhibit three states of matter namely gas, liquid and solid. However, some are more stable in any one state more probably by origin.
Substances in solid state have molecules closely packed without a space to move apart each other. Hence, the energy of molecules in solid state is very low.
In liquid state, molecules have some space to move apart and thus they can flow and have no definite shape like solids. Whereas in gases, molecules are far apart and they are free enough to move and thus have highest energy.
Therefore, water molecules in its vapor state is having highest energy than its liquid state and ice.
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What does that mean about the densities of the phases of water?.
Answers
Answer:
The solid state is the most dense, followed by the liquid state, then the gas state. The solid state is more dense than the liquid state.
Explanation:
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"A daisy is a non-flowering, seed-bearing plant, while a pine tree produces flowers. Both the daisy and the pine tree go through the four major stages of the life cycle, which includes the seed stage, sprouting stage, seedling stage, and the final stage, which is the adult stage. During each stage of the life cycle, the two plants have different shapes and textures. As adult plants, the daisy produces seeds in the cone, and the pine tree produces seeds in the flower."
What statement corrects the errors in Zander's passage? a .A daisy is a flowering plant, and a pine tree is a non-flowering, cone-bearing plant. During the adult stage, the daisy produces seeds in the flower and the pine tree produces seeds in the cone. b.As adult plants, the daisy sprouts seedlings, which are then reproduced. During the adult stage, the pine tree grows spores, which are reproduced. che daisy and the pine tree have different stages in their life cycles. The daisy completes the seedling stage before the sprouting stage. The pine tree has a fertilization stage when seeds are produced. d. The daisy and the pine tree both have the same life cycles, but the daisy produces seeds in the seedling stage, and the pine tree produces seeds in the sprouting stage
Answers
A daisy is a flowering plant, and a pine tree is a non-flowering, cone-bearing plant. During the adult stage, the daisy produces seeds in the flower and the pine tree produces seeds in the cone. So, the correct option is (A).
What are Cones in plants?Cones are also called strobilus. It is oval in shape, containing the reproductive organs of some non-flowering plants. Cones have unique feature of pines and other conifers, also found on all gymnosperms, some club mosses and horsetails.
Male cones produce pollen that is carried by the wind to female cones, after which the female gametes are fertilized by male gametes from the pollen, the female cones produce seeds, which are then scattered away from the plant by wind or animals.
Thus, a daisy is a flowering plant, and a pine tree is a non-flowering, cone-bearing plant. During the adult stage, the daisy produces seeds in the flower and the pine tree produces seeds in the cone. So, the correct option is (A).
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How many 4d electrons would be predicted in the ground state for the following elements?a. zirconiumb. cadmiumc. iridiumd. iron
Answers
In order to answer the question first we must write the atomic number of each element:
Zirconium (Zr): 40
Cadmium (Cd): 48
Iridium (Ir): 77
Iron (Fe): 26
Then, we have to complete the distribution of electrons in each orbital for each atom:
The first 4 levels have the following distribution:
Level1: 1s
Number of electrones: 2
Level 2: 2s, 2p
Number of electrones 8 (2 in the s orbital and 6 in the p orbitals).
Level3: 3s, 3p, 3d
Number of electrones 18 (2 in the s orbital, 6 in the p orbital and 10 in the d orbitals)
Level 4: 4s, 4p, 4d, 4f
Number of electrones 32 (2 in the s orbital, 6 in the p orbitals, 10 in the d orbitals and 14 in the f orbitals)
The order in which the orbitlas are completed depends on the energy of each level. For example the 4s orbitals will be completed before the 3d orbitals because their energy is lower.
The order is as follows:
1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p...
Now, knowing the atomic number we can answer the question:
For Zirconium (total 40 electrones):
\(1s^2,2s^2,2p^6,3s^2,3p^6,4s^2,3d^{10},4p^6,5s^2,4d^2\)2 electrones are predicted in the 4d orbital
For Cadmium (total 48 electrones):
\(1s^2,2s^2,2p^6,3s^2,3p^6,4s^2,3d^{10},4p^6,5s^2,4d^{10}^{}\)10 electrones are predicted in the 4d orbital
For iridium, as it has an atomic number higher than Cadmium we can predict tha it also complets the 4d orbital, then it has also 10 electrones in it.
For iron (total 26 electrones)
\(1s^2,2s^2,2p^6,3s^2,3p^64s^2,3d^6\)Iron has no electrones in the 4d orbitals
The analysis of water in a lake or stream depends upon more than one field of science or body of knowledge. Suppose you stumble across a portable water-testing lab on a riverbank, and you find two testing stations:
1. a light microscope and glass slides
2. a package of pH (acid/base) test strips and a digital thermometer. But you find no scientists.
Test equipment station to the field of science to which it belongs, and hypothesize what is being tested in each station.
Answers
Scientists examined water samples with a light microscope for microorganisms, assessing ecosystem health. pH test strips and a digital thermometer were used for water quality assessment, measuring chemical composition, acidity/alkalinity, and temperature.
1. Light microscope and glass slides:
Field of Science: Microbiology or Biological Sciences
Hypothesis: In this station, the scientists were likely examining water samples under a light microscope. They would prepare slides with the water samples and observe them at a microscopic level. This could involve looking for microorganisms such as bacteria, algae, or other microscopic organisms present in the water. Microbiological analysis of water helps determine the overall health and quality of the ecosystem, as well as potential risks to human or aquatic life.
2. pH (acid/base) test strips and a digital thermometer:
Field of Science: Chemistry or Environmental Science
Hypothesis: In this station, the scientists were likely testing the chemical composition of the water. The pH test strips would be used to determine the acidity or alkalinity of the water, providing information about its overall chemical balance. The digital thermometer would be used to measure the water temperature, which is important in understanding the environmental conditions and potential influences on aquatic life. This type of analysis helps assess the water quality, identify potential pollution sources, and monitor changes in the ecosystem.
It's important to note that these are hypothetical assumptions based on the typical use of the mentioned equipment in water testing. The actual tests being performed could vary depending on the specific objectives and research interests of the scientists involved.
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Specify whether the molecule IFs is polar or nonpolar and explain why.
A. The molecule is polar because all the I-F bonds are polar and the net dipole moment is nonzero.
B. The molecule is polar only because all the I-F bonds are polar.
C. The molecule is nonpolar because all the I-F bonds are nonpolar.
D. The molecule is nonpolar because the sum of all the dipole moments of the I-F bonds is almost zero.
Answers
The molecule is polar because all the I-F bonds are polar and the net dipole moment is nonzero. The correct answer is A.
The polarity of a molecule is determined by the symmetry of its molecular geometry and the polarity of its constituent bonds. In IF₅, the central iodine atom is surrounded by five fluorine atoms in a trigonal bipyramidal arrangement, with two equatorial and three axial positions.
The I-F bonds are polar due to the difference in electronegativity between iodine and fluorine, and the geometry of the molecule does not allow for the dipole moments to cancel out. Therefore, the molecule has a net dipole moment and is polar.
Option A is correct, as it correctly identifies that the molecule is polar due to the polar bonds and non-zero net dipole moment. Option B is incorrect as it does not address the non-zero net dipole moment, while options C and D are incorrect as they state that the molecule is nonpolar, which is not true.
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List at least 5 industries and 5 daily activities that contribute to the build-up of harmful gasses in the atmosphere and one way of combating each of these emission build-ups and then describe the way that your method of combating the build-up of each emission might change the way in which we live.
Answers
Industries that add to the buildup of hazardous gases in the atmosphere include: Transportation (cars, trucks, airplanes, ships) (cars, trucks, airplanes, ships) agricultural production, energy production (coal-fired power plants, oil refineries, and natural gas facilities), and (livestock farming, fertilizer use)
Which three steps can we take to lessen greenhouse emissions and global warming?By generating energy on-site using renewables and other environmentally friendly energy sources, greenhouse gas emissions can be decreased. Rooftop solar panels, solar water heating, small-scale wind power, natural gas or renewable hydrogen-powered fuel cells, and geothermal energy are a few examples.
How can we in Class 8 lessen the greenhouse effect?We must cut back on greenhouse gas emissions if we want to lessen the greenhouse effect. via increasing tree planting and reducing deforestation. Pollution and the greenhouse effect can be reduced by reducing the usage of fossil fuels.
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Net ionic equation for sodium carbonate and sulfuric acids?
Answers
Answer:
CO₃²¯(aq) + 2H⁺(aq —> H₂O(l) + CO₂(g)
Explanation:
The net ionic equation for sodium carbonate (Na₂CO₃) and sulfuric acid (H₂SO₄) can be obtained as follow:
Na₂CO₃ + H₂SO₄ —>
In solution, Na₂CO₃ and H₂SO₄ will dissociate as follow:
Na₂CO₃(aq) —> 2Na⁺(aq) + CO₃²¯(aq)
H₂SO₄(aq) —> 2H⁺(aq) + SO₄²¯(aq)
Na₂CO₃(aq) + H₂SO₄(aq) —>
2Na⁺(aq) + CO₃²¯(aq) + 2H⁺(aq) + SO₄²¯(aq) —> 2Na⁺(aq) + SO₄²¯(aq) + H₂O(l) + CO₂(g)
Cancel out the spectator ions (i.e Na⁺ and SO₄²¯) to obtain the net ionic equation.
CO₃²¯(aq) + 2H⁺(aq —> H₂O(l) + CO₂(g)
Imagine that you heat a pot of water to a boil (212°F), then you turn off the stove and let the water sit there. The room is at room temperature (72°F) What temperature do you predict the water cool to after sitting for 8 hours? (
Answers
Answer:
72 °F
Explanation:
Hello,
In this case, since matter tend the be stable at conditions they do not change, if we have water at room temperature (72 °F) and we heat it until boiling but then we turn off the stove, we molecularly see that due to the heat, the molecules start moving faster and crashing to each other; however when that fed energy starts being removed as the stove gets turned off, the molecules lose energy causing them to start moving slower so they lose energy until a point the remain at the initial status, that is 72 °F because thermal equilibrium is reached. Therefore it is likely for the water to be at 72 °F as well once 8 hours have passed, because a thermal equilibrium is reached with the environmetnal temperature.
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Which of the following would be considered a derived unit? A) length B mass C) density D) temperature
Answers
Answer:
density because it S.I unit is derived from fundamentals
suppose you added 4.000 g of fp sample 1 instead of 2.000 g, what would happen to the freezing point temperature of the water?
Answers
If 4.000 g of sample 1 were added to the water instead of 2.000 g, the freezing point depression of the water would increase.
Freezing point depression is a phenomenon that occurs when a solute is dissolved in a solvent, such as water. The presence of solute molecules in the solvent interferes with the formation of ice crystals, causing the solution's freezing point to decrease. The magnitude of the freezing point depression is directly proportional to the concentration of solute in the solution. This means that if the amount of solute increases, the freezing point depression will also increase. If adding 4.000 g of sample 1 instead of 2.000 g, the concentration of the solute in the water will be higher, leading to a greater depression of the freezing point. This means that the water will freeze at a lower temperature than it would if only 2.000 g of sample 1 were present.
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If 4.000 g of sample 1 were added to the water instead of 2.000 g, the freezing point depression of the water would increase.
What do you mean by Freezing point depression ?Freezing point depression is a phenomenon that occurs when a solute is dissolved in a solvent, such as water. The presence of solute molecules in the solvent interferes with the formation of ice crystals, causing the solution's freezing point to decrease. The magnitude of the freezing point depression is directly proportional to the concentration of solute in the solution. This means that if the amount of solute increases, the freezing point depression will also increase. If adding 4.000 g of sample 1 instead of 2.000 g, the concentration of the solute in the water will be higher, leading to a greater depression of the freezing point. This means that the water will freeze at a lower temperature than it would if only 2.000 g of sample 1 were present.
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Based on your findings, predict whether the following salts are acidic, basic or neutral.
For some of these substances, it may be helpful to refer to the In-Lab Questions on page 60 of your lab manual for the chemical structures. RbC: [Select] LICI: [Select] C6H6NHCl (pyridinium chloride): [Select] K2S: [Select] KNO3: [Select] C7H5NaO2(sodium benzoate): [Select] CH3NH3Br: [Select] NaCN: [Select)
Answers
The salts are classified as: 1. RbCl: neutral, 2. LiCL: neutral, 3. C₆H₆NHCl: acidic, 4. K₂S: basic, 5. KNO₃: neutral, 6. C₇H₅NaO₂: basic, 7. CH₃NH₃Br: acidic, 8. NaCN: basic.
Based on the salts provided, it can be predicted that:-
1. RbCl (Rubidium chloride): This salt is formed from a strong acid (HCl) and a strong base (RbOH), so it is expected to be neutral.
2. LiCl (Lithium chloride): Similar to RbCl, this salt is formed from a strong acid (HCl) and a strong base (LiOH), so it should also be neutral.
3. C₆H₆NHCl (Pyridinium chloride): This salt is formed from a weak base (Pyridine) and a strong acid (HCl), so it is expected to be acidic.
4. K₂S (Potassium sulfide): This salt is formed from a strong base (KOH) and a weak acid (H₂S), so it should be basic.
5. KNO₃ (Potassium nitrate): This salt is formed from a strong acid (HNO₃) and a strong base (KOH), so it is expected to be neutral.
6. C₇H₅NaO₂ (Sodium benzoate): This salt is formed from a weak acid (Benzoic acid) and a strong base (NaOH), so it should be basic.
7. CH₃NH₃Br (Methylammonium bromide): This salt is formed from a weak base (Methylamine) and a strong acid (HBr), so it is expected to be acidic.
8. NaCN (Sodium cyanide): This salt is formed from a strong base (NaOH) and a weak acid (HCN), so it should be basic.
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Consider the following reversible reaction.Upper (s) plus upper O subscript 2 (g) double-headed arrow upper C upper O subscript 2 (g).What is the equilibrium constant expression for the given system?
Answers
Given the reaction:
C + O2 ⇄ CO2
We can find the equilibrium constant (Keq) using the following:
\(k_{eq}=\frac{[products]}{[reactants]}\)\(k_{eq}=\frac{[products]}{[reactants]}\Rightarrow k_{eq}=\frac{[CO_2]}{[C][O2]}\)Therefore the answer is letter A
Study the images of two different fronts.
Item A: Arrows for a cold front and warm front meet with high level, grey clouds. Item B: Arrows for a cold front and warm front are moving in the same direction. The warm front is above the cold front.
Based on arrow movement, why is the front shown in item A different from the front shown in item B?
Warm air rises above cold air in item A, while two air masses collide in item B.
Cold air mixes with warm air in item A, while two air masses barely move in item B.
Warm air is pushed upward near cold air in item A, while a boundary forms in item B.
Two air masses form a boundary in item A, while warm air rises above cold air in item B.
Answers
Answer:
D
Explanation:
The front shown in item A differs from that shown in item B because: D. Two air masses form a boundary in item A while warm air rises above cold air in item B.
What is an occluded front?An occluded front can be defined as a composite weather front that is typically formed during cyclogenesis, which eventually causes a cold front to overtake a warm front and thereby, forcing it aloft with respect to air masses.
This ultimately implies that, an occluded front causes warm air to be mostly separated from a cyclone center that is experienced at the surface of planet Earth.
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If I leave 750mL of 0.50M sodium hydroxide solution uncovered on a windowsill and 150mL of the solvent evaporates, what will the new concentration of the sodium hydroxide solution be
Answers
The new concentration of the sodium hydroxide solution is 0.625 M.
When 150 mL of the solvent evaporates from a 750 mL 0.50 M sodium hydroxide solution.
The new concentration of the sodium hydroxide solution after 150 mL of the solvent evaporates from a 750 mL 0.50 M sodium hydroxide solution can be calculated using the formula:
M1V1 = M2V2
Where: M1 is the initial concentration,
V1 is the initial volume,
M2 is the final concentration,
V2 is the final volume.
We can first calculate the number of moles of sodium hydroxide present in the initial solution using the formula:
n = MV
Where: n is the number of moles
M is the molarity
V is the volume
Thus: n = 0.50 M x 0.750
L = 0.375 mol
Since the number of moles of sodium hydroxide remains constant, we can use this value to determine the new concentration of the solution after the solvent evaporates.
To do so, we can set up the equation as follows:
(0.375 mol)/(0.600 L) = M2
where the final volume is 0.600 L (i.e. 750 mL - 150 mL = 0.600 L).
Solving for M2 gives:
M2 = 0.625 M
Therefore, the new concentration of the sodium hydroxide solution is 0.625 M.
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Explain The element lithium has two common isotopes: Li–6 and Li–7 If the average atomic mass of lithium is 6.94004 u, determine its percent isotopic step by step please urgently
Answers
Answer:
%Li-6 = 5.996% & %Li-7 = 94.004%
Explanation:
let X₁ = Li-6 & X₂ = Li-7 where Xₙ = mole fraction
X₁ + X₂ = 1 => X₁ = 1 - X₂
6·X₁ + 7·X₂ = 6.94004
=> 6(1 - X₂) + 7·X₂ = 6.94004
=> 6 - 6·X₂ + 7·X₂ = 6.94004
=> 6 + X₂ = 6.94004
X₂ = 6.94004 - 6 = 0.94004 => %X₂ = %Li-7 = 94.004%
X₁ = 1.00000 - 0.94004 = 0.05996 => %X₁ = %Li-6 = 5.996%
How does an emerging idea differ from scientific consensus? Which best describes emerging scientific ideas?
Answers
Emerging scientific ideas are new theories or ideas that are gaining attention in the scientific community, but have not yet been fully accepted or confirmed.
Emerging ideas refer to the new and innovative ideas or theories that have yet to gain full scientific acceptance. While a scientific consensus is a view or theory that has been universally accepted and confirmed by multiple experiments or research, an emerging scientific idea is a new and unproven theory or idea that is gaining attention in the scientific community. These emerging ideas may also be referred to as scientific hypotheses. In contrast to scientific consensus, emerging scientific ideas have not yet been subjected to rigorous testing and confirmation.
They are generally proposed to explain new observations or experimental results, which have not yet been fully understood or explained by established scientific theories. Emerging scientific ideas can have the potential to challenge the current scientific consensus. If an emerging scientific idea is found to be valid, it can ultimately lead to the establishment of a new scientific consensus. For example, the emerging scientific idea of the Higgs boson particle led to the discovery of a new field in particle physics, which is now an established scientific consensus.
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explain the movement of the electrons when the splint is in the flame from a bohr model view
Answers
When a splint is held in a flame, the heat energy emitted by the flame causes electrons in the atoms of the splint to gain energy and jump to higher energy levels, according to the Bohr atomic model.
In the Bohr atomic model, electrons are arranged in shells with different energy levels. The electrons closer to the nucleus are in lower energy levels, while those further away are in higher energy levels. When an atom absorbs energy, such as from heat or light, electrons jump to higher energy levels, or shells. As the electrons jump to higher energy levels, they become excited and unstable.
The electrons then lose energy and fall back down to lower energy levels, emitting light of various wavelengths, including visible light. This process is known as atomic emission. The color of the light emitted depends on the amount of energy the electron loses. The Bohr atomic model can explain the movement of the electrons when a splint is held in a flame.
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A sample of oxygen had an initial volume of 4. 0L and was at a standard pressure of 1. 00 atm, what would the new volume be if the pressure was increased to 25. 00 atm?
Answers
Answer: 1.6 L
Explanation:
The new volume of the oxygen would be 0.16L when the pressure is increased to 25.00 atm.
The given problem can be solved using Boyle's law which states that when temperature and no. of moles of gas are constant the pressure is inversely proportional to volume.
let P1 = initial pressure
V1 = initial volume
and P2 = final pressure
V2 = final volume
Then from Boyle's law
P1V1=P2V2
V2=(P1V1)/P2
V2=(1.00atm*4.0L)/25.00atm
V2=0.16L
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A pipe 10 m long and of radius r = 7 cm is to be coated by insulation material to a thickness of dr = 2 mm. Approximate the volume V of insulation material required in m³. Please use pi for л (rather than a decimal approximation) in your answer. Insulation volume (m³): You have not attempted this yet
Answers
The volume of insulation material required is approximately 0.003606 cubic meters (m³).
To calculate the volume of insulation material, we can subtract the volume of the inner pipe (original pipe) from the volume of the outer pipe (original pipe + insulation).
Given:
Length of the pipe, L = 10 m
Radius of the pipe, r = 7 cm = 0.07 m
Thickness of the insulation, dr = 2 mm = 0.002 m
The outer radius of the larger pipe is R = r + dr.
Using the formula for the volume of a cylinder, V = π(R² - r²)L, we can substitute the values and calculate:
V = π((0.07 + 0.002)² - 0.07²) × 10
V ≈ 3.606 × 10⁻³ m³
Therefore, the volume of insulation material required is approximately 0.003606 m³ (cubic meters).
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what is the difference between thermal energy and heat ?
Answers
There is really no difference thermal energy and heat are pretty the same thing.
Answer:
Thermal energy refers to the energy contained within a system that is responsible for its temperature. Heat is the flow of thermal energy.
Hydrated sodium tetraborate is heated
to drive off the water. You find there are
0.01312 mol Na2B4O7 and 0.1311 mol
H2O in the sample. What is the formula
of the hydrate?
A. Na2B4O7 H₂O
B. Na2B4O7 2H₂O
C. Na2B4O7-10H₂O
D. Na2B4O7-13H₂O
Answers
Answer: C. Na2B4O7•10H2O
Explanation:
Hope this helps :)
The formula is tetrasodium borate-Na2B4O7.10H2O
Given- 0.0132 mol Na2B4O7 and 0.1311 mol H2O
Step 1Using the molar mass of the anhydrous Na2B4O7 and its mass percentage, we can calculate the molar mass of the hydrate (if we look at it as 100% of the mass) by stoichiometry.
Molar mass of Na = (22.990 g/mol)
Molar mass of B = (10.811 g/mol)
Molar mass of O = (15.999 g/mol)
Molar mass of Na2B4O7= 2⋅22.990 g/mol +4⋅10.811 g/mol +7⋅15.999 g/mol = 201.217 g/mol
201.217g/mol : 52.8%=x g/mol : 100%
x g/mol = 201.217 g/mol⋅100%÷52.8 %
x g/mol= 381.093 g/mol
Step 2In 381.093 g of hydrate, we have 201.217 g of anhydrous Na2B4O7 , the rest of the mass is water.
381.093g−201.217g= 179.876 g of water
Molar mass of H = 1.008 g/mol
Molar mass of O = 15.999 g/mol
Molar mass of H2O= 1.008 g/mol+ 15.999g/mol = 18.015 g/mol
179.876g ÷18.015 = 9.98= 10 moles of water per mole of hydrate.
URGENT! Please help! Hi, I have to do a titration lab report using the Royal Society of Chemistry online titration lab. Please help me answer the following questions using the observation table I think?
Answers
Answer:
I'm sorry, but I cannot see the observations or the data table you mentioned in your question. However, I can still provide you with some general guidance on how to approach the calculations and answer the questions based on the given information.
4. To calculate the concentration of the NaOH solution, you need to know the mass of NaOH used and the volume of the solution. The formula to calculate concentration is:
Concentration (in mol/L) = (Mass of NaOH (in grams) / molar mass of NaOH) / Volume of solution (in L)
Make sure to convert the mass of NaOH to moles by dividing it by the molar mass of NaOH. The molar mass of NaOH is the sum of the atomic masses of sodium (Na), oxygen (O), and hydrogen (H).
5. The balanced equation for the neutralization reaction between NaOH and HCl is:
NaOH(aq) + HCl(aq) → NaCl(aq) + H2O(l)
(aq) represents an aqueous solution, and (l) represents a liquid.
6a. To calculate the average concentration of HCl in the sample from site B, you need to know the volumes and concentrations of the NaOH and HCl solutions used in the titration. Use the formula:
Concentration of HCl (in mol/L) = (Volume of NaOH solution (in L) * Concentration of NaOH (in mol/L)) / Volume of HCl solution (in L)
Multiply the volume of NaOH solution used by its concentration to find the amount of NaOH used. Then, divide this amount by the volume of HCl solution used to find the concentration of HCl.
6b. To determine the pH of the water at site B, you need to know the concentration of HCl from the previous calculation. The pH can be calculated using the formula:
pH = -log10[H+]
Since HCl is a strong acid, it dissociates completely into H+ ions. Therefore, the concentration of H+ ions is equal to the concentration of HCl. Take the negative logarithm (base 10) of the H+ concentration to find the pH.
To check if the water is safe, compare the calculated pH value to the range provided (pH 4.5-7.5). If the pH falls within this range, the water is considered safe for plant and animal reproduction in an aquatic environment.
6c. Use a similar calculation as in 6a to determine the average concentration of HCl in the sample from site C.
6d. Use the concentration of HCl from 6c to calculate the pH using the formula in 6b. Follow the same procedure to check if the water is safe based on the pH range.
7. To find the most current pH value for the Grand River, you can search for the latest data from reliable sources such as environmental agencies, research institutions, or government websites. Compare this pH value to the pH values obtained in the experiment to assess the difference between them.
Remember, without the specific data and observations, the calculations and comparisons provided here are only general guidelines. It's important to use the actual data from your experiment to obtain accurate results and conclusions.
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Your next-door neighbor has a little girl who is 3 ft, 5 inches tall. What is the little girl’s height measured in inches? in decimeters?
Answers
Answer:
41 inches
Explanation:
There is 12 inches in 1 foot so times 12 and 3. Thats 36 so now do 36 + 5 that =41.
According to VSEPR theory, if there are two electron domains on a central atom, they will be arranged such that the angles between the domains are __________. a. 360° b. 120° c. 90° d. 180° e. 109.5°
Answers
Answer:
Option d is correct
Explanation:
The basis of the VSEPR model of molecular bonding is that to minimize repulsions, electron domains in the valence shell of an atom arrange on their own.
According to VSEPR theory, if there are two electron domains on a central atom, they will be arranged such that the angles between the domains are 180°
A base used in baking cake is
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Answer:
sodium bicarbonate, potassium bicarbonate and ammonium bicarbonate are the most commonly used bases.
Write a paragraph on how buffer solutions play an important role in regulating blood acidity.
PLEASE HELP
Answers
Answer:
Buffer solutions are essential in regulating blood acidity because they help maintain a stable pH level in the body. The pH of blood needs to be tightly controlled within a narrow range of 7.35 to 7.45 for optimal physiological functioning. Buffers work by absorbing excess hydrogen ions (H+) or hydroxide ions (OH-) that may be introduced into the bloodstream from various metabolic reactions. For example, if the blood becomes too acidic due to an increase in H+ ions, buffer systems such as the bicarbonate-carbonic acid system can neutralize the excess H+ ions and restore the pH balance. Conversely, if the blood becomes too alkaline due to an increase in OH- ions, buffer systems can absorb the excess OH- ions and bring the pH back to normal. In this way, buffer solutions help maintain the delicate acid-base balance crucial to the proper functioning of our bodies.