Taking into account the definition of enthalpy of a chemical reaction, the value of ΔH for C + 3D → A + 2B is -157 kJ.
Definition of enthalpy of a chemical reactionThe enthalpy of a chemical reaction as the heat absorbed or released in a chemical reaction when it occurs at constant pressure. That is, the heat of reaction is the energy that is released or absorbed when chemicals are transformed into a chemical reaction.
A negative value of an enthalpy change indicates an exothermic reaction; a positive value of ΔH indicates an endothermic reaction.
Reversing the direction of a chemical equation changes the arithmetic sign of ΔH because a process that is endothermic in one direction is exothermic in the opposite direction.
Value of ΔH in this caseIn this case, the balanced reaction is:
A + 2B → C + 3D
and the enthalpy reaction ∆H° has a value of 157 kJ and it is an endothermic reaction.
To calculate the value of ΔH for C + 3D → A + 2B, you can see that the reaction is inverted, being in this case an exothermic reaction. Then, the enthalpy value must be reversed from sign.
Finally, the value of ΔH is -157 kJ.
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5 cm³ is a small volume of water for each experiment.
Give one advantage and one disadvantage of using a larger volume.
A smaller volume of an experiment, like 5 cm³, does not lead to wastage of the product and does not alter the testing procedures.
Why should the volume be controlled in an experiment?
The variable, like volume, is regulated (or maintained at the same level) to conduct a fair test. In this case, the object's volume can be altered. The mass of the substance will increase as the volume does. The quantity of atoms inside an object increases with its volume.
Advantage
The margin of error decreases with increasing study sample size. The risk of reporting false-negative or false-positive results can be reduced by researchers by using a larger volume. The accuracy of results will increase as the number of samples increases.
Disadvantage
It takes longer to gather, thus burdening the people collecting the larger volume of samples. In some circumstances, likely, the collection deadline will negatively impact how smoothly the production line runs.
Hence, there are both advantages and disadvantages of using a larger volume.
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what volume in liters of fluorine gas is needed to form 639 l of sulfur hexafluoride gas if the following reaction takes place at 2.00 atm and 273.15 k: s(s) 3f₂(g) → sf₆ (g)?
For producing 639L of [tex]SF_6[/tex], a volume of 1916.96L of [tex]F_2[/tex] gas is required for the reaction.
If the pressure and temperature at which the reaction occurs is known, we may use the ideal gas law to compute the stoichiometry of processes involving gases by using the connection between the volume (in liters) and quantity of gases (in moles). A chemical reaction's volume of gas can be evaluated by collecting it in an inverted vessel filled with water. The gas pushes water out of the vessel, and the amount of liquid displaced is proportional to the amount or volume of gas.
Given:
Volume of [tex]SF_6[/tex] = 639L
Pressure, P = 2atm
Temperature, T = 273.15K
To find:
Volume, V of [tex]F_2[/tex] gas = ?
Formula:
PV = nRT
Calculations:
No. of moles of [tex]SF_6[/tex] = 2 x 639 / 0.082 x 273.15
No. of moles of [tex]SF_6[/tex] = 57.057 moles
[tex]S (s) + 3F_2 (g) \rightarrow SF_6 (g)[/tex]
From the reaction,
1 mole of [tex]SF_6[/tex] is formed from 3 moles of [tex]F_2[/tex]
Therefore,
No. of moles of [tex]F_2[/tex] = 3 x 57.057 = 171.171 moles
Volume of [tex]F_2[/tex] = 171.171 x 0.082 x 273.15 / 2
Volume of [tex]F_2[/tex] = 1916.96L
Result:
1916.96L of [tex]F_2[/tex] gas is required to produce 639L of [tex]SF_6[/tex].
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what does removing energy from water at 25c do to the temp of the water?
Removing energy from water at 25 °C the temp of the water will decreases.
When we remove the heat from water the temperature of water will falls and water will cool down. The water is cool; down when we remove the heat from it and the kinetic energy decreases of the particles. once the temperature recaches to the freezing point then there will be no further change in temperature. This is the phase transition from liquid to solid. By the removal of heat will cause the particle of water to locking up into place.
Thus, Removing energy from water at 25 °C the temp of the water will decreases.
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what is the proper method to determine the mass number of an isotope
Answer:
Subtract the atomic number (the number of protons) from the rounded atomic weight. This gives you the number of neutrons in the most common isotope. Use the interactive periodic table at The Berkeley Laboratory Isotopes Project to find what other isotopes of that element exist.
Explanation:
Forms of the same atom that differ only in their number of neutrons are called isotopes. Together, the number of protons and the number of neutrons determine an element's mass number: mass number = protons + neutrons.
The drawing below shows the effect of moving air on a desert sand dune.
Which most likely describes the event in the drawing?
The drawing below shows the effect of moving air on a desert sand dune.
Which most likely describes the event in the drawing?
It is an example of erosion by gravity.
It is an example of erosion by wind.
It is an example of physical weathering by wind.
It is an example of physical weathering by gravity.
The drawing below shows the effect of moving air on a desert sand dune describes the event in the drawing it is an example of erosion by wind
Natural sand dunes usually start as windblown sand that accumulates in a sheltered area behind some type of obstacle such as piles of seaweed and a hill of sand made up of wind on the coast or in a desert and it is because of erosion by wind strong winds blow across the loose sand on the surface of the earth including sands found in deserts and beaches that's why erosion by wind most likely describes the event in the drawing
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Select the choice that best describes the relationship of the pair of compounds. you might find it helpful to make a model of ceach. two compounds. compound 1 has an isopropyl group pointing up and an ethyl group pointing to the lower left. pointing to the right is a wedged bond to hydroxy and a dashed bond to methyl. compound 2 has an ethyl group pointing up and an isopropyl group pointing to the lower left. pointing to the right is a wedged bond to methyl and a dashed bond to hydroxy. the compounds are: enantiomers constitutional isomers not isomeric the same compound
The compounds are enantiomers.
Enantiomers are pairs of compounds that have exactly the same connectivity but opposite three-dimensional shapes. Enantiomers are not the same. One enantiomer cannot be superimposed on top of the other. Enantiomers are mirror images of each other. The easiest way to distinguish between enantiomers is to recognize that two molecules are mirror images of each other.
Enantiomers must be mirror images. The molecules in the image above are reflected on a thick line representing a specular surface. Examples of enantiomeric pairs of substances are the two optically active forms of tartaric acid called d-tartaric acid and l-tartaric acid. Stereoisomers that are mirror images of each other and are not superimposable are called enantiomers. Molecules whose mirror images are not superimposable and exist as enantiomeric pairs are said to be chiral and exhibit chirality.
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2. Which metal reacted most vigorously when placed in the acid? Give evidence to
support your answer.
Answer:
The alkali metals (Li, Na, K, Rb, Cs, and Fr) are the most reactive metals in the periodic table – they all react vigorously or even explosively with cold water, resulting in the displacement of hydrogen.
Explanation:
The metal that reacted most vigorously when placed in the acid is sodium, as it is an alkali metal.
What are alkali metals?At standard temperature and pressure, all of the bright, soft, extremely reactive alkali metals rapidly shed their outermost electron to create cations with charge +1.
One of the most reactive metals is the alkali metal. They have greater atomic radii and low ionization energies, which contribute to this. They have an oxidation state of 1, and they frequently give electrons during reactions. These metals stand out for their supple texture and silvery hue.
The alkali metals (Li, Na, K, Rb, Cs, and Fr) are the most reactive metals in the periodic table – they all react vigorously or even explosively with cold water, resulting in the displacement of hydrogen.
Therefore, the correct option is d. sodium.
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The question is incomplete. Your most probably complete question is given below:
Oxygen
magnesium
iron
sodium
please help me on this question
Answer:
c
Explanation:
ch4 + 4cuo --> CO2 + 2h20 + 4cu
when enzyme solutions are heated, there is a progressive loss of catalytic activity over time due to denaturation of the enzyme. a solution of the enzyme hexokinase incubated at 45 ∘c lost 50% of its activity in 12 min, but when incubated at 45 ∘c in the presence of a very large concentration of one o
Both the substrates as well the enzymes do not undergo denaturation since the enzyme was incubated with the substrate and it lost its activity.
When a certain substrate comes into contact with an enzyme, it will bind to the active region. Binding of the substrate to the active region of the protein results in the formation of a more stable enzyme substrate complex. This is because the enzyme substrate complex is more resistant to heat denaturation than just the enzyme.
Because the enzyme-substrate complex ground state has a lower energy level, more energy is required to overcome this energy barrier and denature the enzyme. In the question, it is given that 3% of the enzyme lost its activity, which might have happened when the enzyme and the substrate were incubated. Only 3% of the enzyme was liberated after the denaturation step, leaving 97% occupied with substrate.
As a result, neither the enzyme nor the substrate undergoes denaturation.
The image has the complete question
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Min was writing about changes in the state of matter for a research paper. Which of these changes might she include as examples of sublimation? Choose the two statements that apply.
The correct option is D. Dry ice changes directly to carbon dioxide gas
A material can move straight from the solid to the gas state by sublimation without going through the liquid state. The triple point on a material's phase diagram corresponds to the lowest pressure at which the substance can remain as a liquid, and sublimation is an endothermic process that takes place there. Deposition, also known as desublimation, is the opposite of sublimation, in which a material transitions straight from the gas phase to the solid phase. A solid-to-gas transition (sublimation) followed by a gas-to-solid transition has also been referred to as sublimation (deposition)
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complete question:
Min was writing about changes in the state of matter for a research paper. Which of these changes might she include as examples of sublimation?
Choose the two statements that apply.
A. Clothing is hung outside on a day when the temperature is below the freezing point of water. The clothes dry, even though they freeze first.
B. An ice cube melts on the floor, then it evaporates.
C. Bromine is a reddish brown, liquid element. In a closed container, a reddish brown gas exists above the surface of the bromine.
D. Dry ice changes directly to carbon dioxide gas
a person with cystic fibrosis typically contains 60-200 mm cl- in samples of their perspiration. the chloride in a 1.0 ml aliquot of such a sample is to be measured by combining it with 1.0 ml of a reagent containing 0.0250 m agno3. ksp
In the diagnosis of cystic fibrosis caused by gene mutation, the mass of AgCl formed and the mass of [tex]Cl^-[/tex] remaining are 0.003583g and 0.006203g respectively, and the % of [tex]Cl^-[/tex] precipitated is 12.5%.
Cystic fibrosis (CF) is a hereditary condition that causes respiratory and gastrointestinal issues. An alteration (mutation) in the gene that produces the cystic fibrosis transmembrane regulator (CFTR) protein causes cystic fibrosis. To be born with CF, a new born must get two copies of the CF gene, one from each parent.
Cystic fibrosis causes thick, sticky mucus to accumulate in the lungs. CF causes recurring lung infections and makes breathing difficult over time. Other organs of the body, like the pancreas, might be affected by Cystic fibrosis, making it difficult to digest meals and maintain a healthy weight.
a) Mass of AgCl precipitate = no. of moles x molecular mass
Mass = 0.025mol/L x 0.001L x 143.32g/mol
Mass = 0.003583g
b) Mass of [tex]Cl^-[/tex] remaining in solution after precipitation = no. of moles x molecular mass
No. of moles of [tex]Cl^-[/tex] = 0.2mol/L x 0.001L = 0.0002 mol
No. of moles of [tex]Ag^+[/tex] = 0.25mol/L x 0.001L = 0.000025 mol
Mass of [tex]Cl^-[/tex] remaining = (0.0002 – 0.000025) x 35.45
Mass of [tex]Cl^-[/tex] remaining = 0.006203g
c) % of [tex]Cl^-[/tex] precipitated = 0.000025 / 0.0002 x 100 = 12.5%
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What formed a channel on mars?
Continental drift is a geologic process that forms channel on Mars.
Continental drift, the same process that creates contemporary channels like the mid-Atlantic channel or the African Rift Valley, is the geologic process that is most likely to have created the channel on Mars. Massive troughs that are visible from orbit are being exposed when Mars' tectonic plates separate. Similar to Earth, Mars too experiences gradual continental drift, which moves by less than an inch per year and is much too slow for any person to notice. However, this can lead to significant geological and geographic changes over millions of years that modify the planet's surface.
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1. What type of TV uses a CCFL for backlighting?
O 3D
O LCD
OLED
O Cathode Ray tube
Explanation:
When a virus infects a bacterial cell, often new viruses are assembled and released when the host bacterial cell is lysed. If these new viruses go on to infect new bacterial cells, the new host cells may not be lysed. What is the most plausible explanation for this?A) The bacterial cell must be resistant to infection by the virus.
B) The virus carries genes that confer resistance to the host bacterial cell.
C) The host bacterium couples the viral infection with transformation.
D) The virus has entered the genome of the bacterial cell and is in the lysogenic stage.When a virus infects a bacterial cell, often new viruses are assembled and released when the host bacterial cell is lysed. If these new viruses go on to infect new bacterial cells, the new host cells may not be lysed. What is the most plausible explanation for this?A) The bacterial cell must be resistant to infection by the virus.B) The virus carries genes that confer resistance to the host bacterial cell.
C) The host bacterium couples the viral infection with transformation.
D) The virus has entered the genome of the bacterial cell and is in the lysogenic stage.Answer:
LCD TV's use a CCFL for backlighting
some ammonia is sealed in a container and allowed to equilibrate at a particular temperature. the reaction is endothermic. 2nh3(g) ↔ n2(g) 3h2(g) in which direction will the reaction occur if ammonia is added to the system?
If ammonia is added to the system, the reaction will shift to the right, in favour of the forward direction.
A reaction is said to be at equilibrium when the concentration of reactants is equal to the concentration of the products. This means that the rate at which reactants are forming products is equal to the rate at which products are changed back to reactants.
All reactions at equilibrium follow Le Chatelier's principle, which states that if a chemical system in equilibrium is disturbed by changing the conditions (such as concentration, temperature and pressure changes), the position of equilibrium shifts to the left or to the right in order to counteract the change and to re-establish an equilibrium.
This means that if certain factors in a chemical reaction at equilibrium is changed, the reaction will shift either to the left or to the right. If it shifts to the left, the backward reaction is favoured and more reactants are produces, but if it shifts to the right, the forward reaction is favoured, and more products are produced.
In the question above, ammonia (2NH₃) is added to the chemical system. This will cause an increase in the concentration of ammonia; hence, more ammonia will be converted to nitrogen and hydrogen in order to decrease the concentration of ammonia and re-establish equilibrium. This causes the reaction to shift to the right.
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problem 2 (10 pts).2.00 gram-moles of dichloromethane are contained in a vessel at 100. °c and 12.0 atm. a. 5pt) what is the system volume (l) based on the ideal gas equation? b. 5pt) suppose the actual volume of the vessel is 4.50 liters. what percentage error results from assuming ideal-gas behavior?
The volume of the system is found to be 5.097L and the % error is found to be 13.2%.
Every three-dimensional item requires some amount of space. The volume of this space is measured. Volume is defined as the space occupied by an item inside the confines of three-dimensional space. It is also known as the object's capacity. Volumes change depending on the form.
The absolute value of the difference between the measured and actual values is divided by the actual value and multiplied by 100 is the % error. Percent mistakes indicate the magnitude of your errors while measuring anything in an experiment. Smaller numbers of % error indicate that you are getting nearer to the acceptable or true value.
Given:
P = 12atm
n = 2 moles
T = 100℃ = 100 + 273 = 373K
To find:
(a) V = ?
(b) % error = ?
Formula:
PV = nRT
% error = (experimental – actual) / actual x 100
Calculations:
(a) V = nRT/P
V = 2 x 0.082 x 373 / 12
V = 5.097L
(b) % error = (5.097 – 4.5) / 4.5 x 100
% error = 0.597 / 4.5 x 100
% error = 0.132 x 100
% error = 13.2%
Result:
The system’s volume is 5.097L and the % error is 13.2%.
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URGENT!!!!
Part D: Challenge
An unknown mixture is set in beaker on the teacher's table. Describe the five different parts of the
mixture and how we can separate it.
An unknown mixture is set in beaker on the teacher's table the five different parts of the mixture and we can separate it by method evaporation, distillation, sedimentation, and filtration
Mixture is the composed of one or more pure substances in varying compositions called as mixture and unknown mixture is separated by shake the separatory funnel to allow intimate mixing of the solutions and effect extraction of the compound from the organic mixture and mixture can be physically separated by sedimentation process, filtration, crystallization, distillation, diffusion, panning, magnetic separation, and adsorption are a few of the methods used to separate materials and the substance is said to be pure when a sample of it has purified all other type of material
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Which phase of matter is the least common on Earth?
A. Gases
B. Liquids
C. Solids
D. Plasma
Answer:
the answer is....... D. Plasma
Answer:
Plasma
Explanation:
Got it right
If 100. 0 ml of a 0. 500 m aqueous hydrazine is mixed with 100. 0 ml of 0. 500 m aqueous hydrochloric acid, what will be the ph of the resulting solution?.
The pH of the resulting solution when 100. 0 ml of a 0. 500 m aqueous hydrazine is mixed with 100. 0 ml of 0. 500 m aqueous hydrochloric acid is 4.54
Since hydrazine is a weak base and hydrochloric acid is a strong acid.
No. of moles of hydrazine =( 100 × 0.500 ) mmol
= 50 mmol
No. of moles of hydrochloric acid =( 100 × 0.500 )
= 50 mmol
Since the number of mmol of base and acid is equal. Hence complete neutralization will take place because acid and base react in 1 : 1 mol ratio.
So after neutralization, a salt will be formed which will be acidic in nature because salt formed by the neutralization of strong acid and weak base will be acidic in nature.
Hence pH will be less than 7. Because an acidic solution has pH less than 7 .
The Kb is 3.0x10^-6
pKb=-logKb
pkb=-log(3.0x10^-6)
pkb=5.2287875
The concentration of salt is 50/200=0.25 M
pH=7-1/2pKb-logC
pH=7-1/2(5.2287875)-1/2log(0.25)
pH=4.54
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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
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.
Which statement is correct in the process of balancing the equation?
The correct statement in the process of balancing the equation is option C which is Do nothing, the equation is already balanced.
The chemical equation which is given in the question is -
CH₄ + O₂ → CO₂ + 2 H₂O
This reaction is a balanced chemical reaction as number of atoms of product and reactant are equal.
Number of carbon atoms on reactant side is 1 and number of carbon atoms on product side is also 1. Number of oxygen atoms on product side is 2 and hydrogen atoms is 4 and on reactant side, number of oxygen atom was 1 and number of hydrogen atom was 2 but after adding coefficient 2 in front of H₂O, number of Oxygen atoms became 2 and number of hydrogen atom became 4 making it a balanced reaction.
Therefore, correct option for process of balancing the equation is C.
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consider the reaction when aqueous solutions of ammonium phosphate and chromium(ii) sulfate are combined. the net ionic equation for this reaction is:
Explanation:
The reaction of aqueous solutions of iron(II) sulfate and ammonium phosphate leads to the formation of solid precipitate of iron phosphate and an aqueous solution of ammonium sulphate.
Molecular equation :
3
F
e
(
S
O
4
)
(
a
q
)
+
2
(
N
H
4
)
3
P
O
4
(
a
q
)
→
F
e
3
(
P
O
4
)
2
(
s
)
+
3
(
N
H
4
)
2
S
O
4
(
a
q
)
Total ionic equation :
3
F
e
+
2
(
a
)
+
3
(
S
O
4
)
2
−
(
a
q
)
+
6
(
N
H
4
)
+
(
a
q
)
+
2
P
O
3
−
4
(
a
q
)
→
F
e
3
(
P
O
4
)
2
(
s
)
+
6
(
N
H
4
)
+
(
a
q
)
+
3
S
O
2
−
4
(
a
q
)
Net ionic equation :
By canceling the spectator ions from total ionic equation, we get
3
F
e
+
2
(
a
q
)
+
2
P
O
3
−
4
(
a
q
)
→
F
e
3
(
P
O
4
)
2
(
s
)
iodine is one of many compounds that can be used as a stain for tlc, however, there are many stains that can be used to identify specific functional groups. looking online, propose a good tlc stain to identify dehydroabietylamine on a tlc plate?
The iodine staining technique is one of the methods that can be used as a stain for TLC, however, there are many stains that can be used to identify specific functional groups.
The iodine staining technique allows us to carry abound a marked version of owe 'TLC' sun rather than having to pencil sketch ow spots in the UV views. Fore compounds might not even appear under Uv light, making otter visualization ted. such as iodine staining necessary.One of the first techniques for displaying organic chemicals was to stain a TLC plate with iodine vapor. The discovery that iodine has a strong affinity for both unsaturated and aromatic molecules forms the basis for this theory.Iodine is one of the substances that can be used as a TLC stain, however, there are numerous stains that can be used to identify particular functional groups. Iodine sublimes and interacts with the compounds on a produced TLC plate when the chamber is sealed, creating yellow-brown patches.Learn more about TLC stain at:
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if 1.00 x 1018 singly charged positive sodium ions flow from the anode of an electrochemical cell each second and an equal number of singly charged negative chlorine ions flow from the cathode of the cell, how much current flows through the cell?
Total current flows through the cell I = 0.32 Amp
What is electrochemical cell?An electrochemical cell is a device that either generates energy from chemical reactions inside of it or uses electricity to power various chemical processes inside of it.
Given,
Sodium ion flows from anode and negatively charged ion flowing from cathode
so if you write the equation that will be
Na - e ⇄ Na⁺
Cl⁻ + e ⇄ Cl
Now current flowing is the number of charges flowing per unit second
here total current is due to cation (Na⁺) and anion (Cl)
so only one electron is associated here,
so total current (I) = 10¹⁸ ˣ 1.6 ˣ 10⁻¹⁹ Amp.
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In two to three sentences, explain the trend for atomic size. Why does this trend occur?
Answer:
Atomic Size Trend Across the Period
This is caused by the increase in the number of protons and electrons across a period. One proton has a greater effect than one electron cause of the coulombic law. Thus, electrons are pulled towards the nucleus, resulting in a smaller radius.
Explanation:
9. given that methane (aka. natural gas, ch4) has a fuel value of 55.5 mj/kg and hydrogen (h2) has a fuel value of 142 mj/kg, compare and contrast these fuels with the best combination determined by the class.
From the comparison of methane and hydrogen gases, it is found that Hydrogen gas, H₂ will be the best fuel
From the given question, we have:
CH4 and H₂ have fuel values as following;
For CH4=55.5mj/kg
For H[tex]_{2}[/tex]=142mj/kg
When we combust CH4 It will produce CO[tex]_{2}[/tex] gas and water as a product. The CO[tex]_{2}[/tex] gas is an environment pollutant and it also has low fuel value
However, if we combust H₂, It will produce only H₂O, which is environmentally healthy and also produces more fuel value.
Hence, H₂ will be the best fuel
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Alan and Faisyal are talking about why pieces of two different metals that are the same size have very different masses. Alan says that the particles must be different masses, and Faisyal says that it is to do with how the particles are arranged. Are they correct? What would you say to them?
Yes, Alan and Faisyal are both correct. Two metals or objects can have the same outward structure but different masses. This is because of the way their atoms or particles are arranged. The way in which the particles of matter are arranged is called Density.
What is the density of Matter?The degree of compactness of a substance is measured by its density. It is the amount of mass per unit volume that determines the degree of uniformity. It is the connection between a substance's mass and the quantity of space it takes up.
The density of a material is its mass per unit volume. The most common sign for density is ρ, however, the Latin letter D can also be used. Density is defined mathematically as mass divided by volume.
The formula for density is given as ρ= m/V, where is the density, m is the object's mass, and V is the object's volume. The density of an item is defined as its mass per unit volume. The kilogram per cubic meter (kg/m3) is the SI unit of density.
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Ben is at the beach by the sea with his parents. After swimming, he dried off in the sun and discovered small, salty tasting white crystals on his skin. Explain what happened.
Answer:
what happened was when he dried off, there was still a little salt water on him. so, since the water has salt in it and the sun is very hot wich makes salty dried up as hard salt on him.
How many meters below sea level results in 1 atm of additional pressure?
O 10 feet
O 33 feet
O 10 meters
O 33 meters
10 meters below sea level results in 1 atm of additional pressure.
The pressure increases about one atmosphere for every 10 meters of water depth.
We know,
1 atm pressure = 1.01325 bar equation1
Gravitational acceleration = 9.81 [tex]m/s^{2}[/tex] equation2
Density of water = 1000kg/[tex]m^{3}[/tex] equation3
P = (density of water) (gravitational acceleration) (height under water)
Substitute values from equation1 , equation2 and equation3 in formula of pressure under water.
P = (1000) (9.81) (10.33)
P = 101325 Pa(Pascal) (1bar = [tex]10^{5}[/tex] Pascal)
Now we need to convert Pascal to Bar using the relation (1bar = [tex]10^{5}[/tex] Pascal).
P = 1.01325 bar
Thus we can conclude that 10 meters below sea level results in 1 atm of additional pressure.
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The hybridization scheme employed by a central atom when forming more than four bonds is.
The hybridization scheme employed by a central atom when forming more than four bonds is sp3d
Hybridization is the mixing of orbitals of different energies to give hybrid orbitals of the same energy.The hybridization sp3d employs five orbitals which can be paired to give the corresponding compound.It involves the mixing of 1s orbital, 3p orbitals, 3p orbital, and 3d orbital to form orbitals of equal energy.An example is PCl5 and it follows trigonal bipyramidal geometry. It has axial and equatorial bonds.It takes place in the presence of weak field ligands.The complex formed by sp3d hybridization is known as the outer orbital complex.To learn more about hybridization visit:
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Explain why one must use the absolute temperature scale to solve gas problems.
For ease of use, the temperature was set to zero degrees Celsius. The velocity of particles is represented by zero on the absolute (Kelvin) scale. Absolute temperature changes cause corresponding changes in pressure or volume.
Temperature is a physical parameter that describes how hot stuff or radiation is.
such as the SI scale; those that rely solely on purely macroscopic properties and thermodynamic principles, such as Kelvin's original definition; and those that are not defined by theoretical principles but are defined by convenient empirical properties of particulate matter.
A thermometer is used to measure temperature.
The coldest a body can be conceived to be is one with an absolute zero temperature. It can only be approximated extremely closely, but not actually reached, in experiments.
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