Samples A and B are metals, and samples C and D are nonmetals.
What is the nature of the materials?We have to note that the appearance of the object can be used to determine the kind of object that it is. We know that a metal would always have a luster and the exception here is only mercury that is a liquid metal.
On the other hand, the non metals are either liquid or they are solids that are brittle and would have a low melting and boiling point due to the lack of a crystalline structure.
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Are CO2 and SO2 polar or nonpolar?.
Answer:
Polar and nonpolar
Explanation:
CO2 is a nonpolar molecule meaning it has equal sharing of electrons
SO2 is a polar molecule meaning that the oxygen pulls slightly more giving it a more bent shape as it has a more negative and a more postive side
The fact that most compounds of this chemical class with synthesized from the combination of carbon and water accounts for the derivation of the term
Carbohydrate. The word derives from the fact that the majority of compounds in this chemical class are produced from the combination of carbon and water.
Water is a compound because it is made up of two elements: hydrogen and oxygen. Water, on the other hand, is not the same as oxygen or nitrogen. While water is a liquid, oxygen and nitrogen are gases. To be more specific, all quantitative estimates are made for glucose, the most important hexose in human metabolism. Organic compounds are those with a carbon atom backbone, whereas all other compounds are classified as inorganic. Carbohydrate. The word derives from the fact that the majority of compounds in this chemical class are produced from the combination of carbon and water.
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if you use too much hot solvent when dissolving your crude compound, how will that impact the recovery of your compound and why?
If you use too much solvent, the solution may become too dilute to produce crystals. It is critical to gradually chill the flask in room temperature and finally in ice water.
Impurities will be trapped within the crystal in a hurried crystal formation. In addition, the resultant crystals will be smaller.A solvent is a substance that dissolves a solute, resulting in a solution. A solvent is often a liquid, although it can also be solid, gas, or supercritical fluid. Water is a polar molecular solvent and the most commonly employed solvent by living ; all ions and proteins in a cell are dissolved in water within the cell.Solvents are used in paints, paint removers, inks, and dry cleaning. Organic solvents are used in dry cleaning (for example, tetrachloroethylene); paint thinners (toluene, turpentine); nail polish removers and glue solvents (acetone, methyl acetate, ethyl acetate); spot removers (, petrol ether); detergents (citrus ); and scents.
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Name one change Jane could make to her experiment to produce the maximum amount of chalk(CaCO3). [1 mark]
Add an e______ of calcium______.
Add an excess of calcium hydroxide (Ca(OH)₂).
What is the chalk about?Adding an excess of calcium hydroxide (Ca(OH)₂) to the experiment would help to produce the maximum amount of chalk (CaCO₃). Calcium hydroxide is a strong base that can react with carbon dioxide (CO₂) in the air to produce calcium carbonate (CaCO₃).
This reaction is exothermic, meaning it releases heat, which speeds up the reaction. By adding an excess of calcium hydroxide, Jane would ensure that there is enough of the reactant to react with all of the carbon dioxide present in the air and form the maximum amount of chalk.
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4. How many liters of gas are found in a balloon that contains 1.34x1025 molecules of gas at
Standard temperature and pressure
a. There are 22.4 L of gas in 1 mole at STP
At standard temperature and pressure (STP), one mole of a gas occupies a volume of 22.4 liters is 0.22 Liters.
How to determine standard temperature and pressure?To determine the number of liters of gas in a balloon containing a certain number of gas molecules, we can use the ideal gas law. To convert from the number of molecules to the number of moles, we can use Avogadro's number, which is the number of atoms or molecules in one mole of a substance. Avogadro's number is 6.022 x 10^23 atoms or molecules per mole.So, to find the number of moles of gas in the balloon, we can divide the number of molecules of gas by Avogadro's number:1.34x10^25 molecules / 6.022x10^23 molecules/mole = 2.23 molesTherefore, using the Ideal gas law, we can find the volume of the gas in the balloon at STP:V = nRT/PV = 2.23 * 8.314 J/mol.K / 101.325 kPa = 0.22 Liters.One mole of a gas occupies a volume of 22.4 liters at STP.Avogadro's number is the number of atoms or molecules in one mole of a substance, and is approximately 6.022 x 10^23 atoms or molecules per mole.The number of moles of gas in the balloon can be found by dividing the number of molecules of gas by Avogadro's numberUsing the Ideal gas law, we can find the volume of the gas in the balloon at STP, which is 0.22 Liters.To learn more about standard temperature refer:
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Why NH3 is polar but PH3 is nonpolar?.
NH3 is polar because it has a trigonal pyramidal molecular geometry and the nitrogen atom has a higher electronegativity than the hydrogen atoms, giving it a partial negative charge and the hydrogen atoms a partial positive charge.
This creates a dipole moment, making NH3 a polar molecule.
On the other hand, PH3 is nonpolar because it has a tetrahedral molecular geometry and the phosphorus and hydrogen atoms all have the same electronegativity, so there is no dipole moment and no net separation of charge. Thus, PH3 is a nonpolar molecule.
The polarity of a molecule depends on its molecular geometry and the electronegativity of its atoms. The polar NH3 has a trigonal pyramidal shape with a more electronegative nitrogen atom, while the nonpolar PH3 has a tetrahedral shape with atoms of the same electronegativity.
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a bond that forms between an electronegative atom and a hydrogen atom with a positive dipole____
A bond that is formed between an electronegative atom and a hydrogen atom with a positive dipole is called a Hydrogen Bond.
Hydrogen bonding is a special and important type of dipole-dipole attraction between molecules, unlike a covalent bond, to a hydrogen atom. It results from the attractive force existing between a hydrogen atom covalently bonded to a very electronegative atom such as a Nitrogen, Oxygen, or Fluorine atoms or any other very electronegative atom. Hydrogen bond strengths range from 4 kJ(kilojoule) to 50 kJ per mole of hydrogen bonds.
In molecules containing bonds of N-H, O-H or F-H, the large difference in electronegativity between the H atom and the other atoms of N, O or F leads to a highly polar covalent bond (i.e., a bond dipole).
Because of the difference in electronegativities of the atoms, the H atom bears a large partial positive charge and the other electronegative atoms of N, O or F bear a large partial negative charge.
Some examples of molecules or compounds having hydrogen bonding are as follows.
Water - A water molecule is composed of a highly electronegative atom of oxygen linked to the polar positive hydrogen atom.Ammonia - The hydrogen bonds in ammonia (NH3) molecule are formed between nitrogen and hydrogen atoms.Hydrogen FluorideCarboxylic Acid, etc.Learn more about Hydrogen Bond here:
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In area of higher core, what help you maintain healthy behavior? Conider your peronal knowledge about what it mean to be healthy and your attitude and belief. Then conider the other level of the ocioecological model—conider how you are upported by friend and family, your chool community and living ituation, intitution to which you belong, and local or national policie
A healthy behavior can be maintained by maintaining healthy relationships with supportive friends and family, keeping good hygiene, having enough sleep, exercising etc.
Maintaining a healthy behavior is very important not just for our emotional and mental health but also for our overall physical as well as social well being too. Our behavior reflects our attitude as well as our beliefs.
A healthy behavior can be maintained by healthy social interaction amongst our peers, supportive friends, family and also in the community as well as institution which we are a part of. One can also maintain healthy behavior by adopting healthy habits like exercising, sleeping on time, keeping good hygiene etc.
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Which layer of the atmosphere is chemically stratified, with the lightest molecules riding above heavier molecules?a. the thermosphereb. the tropospherec. the mesosphered. the stratosphere
The stratosphere is the most chemically stratified layer in the atmosphere.
What is the stratosphere?
The stratosphere is the layer of the atmosphere that is chemically stratified, with the lightest molecules riding above heavier molecules. The ozone layer, which contains a high concentration of ozone (O3) molecules, is located in the stratosphere.
The stratosphere is located above the troposphere and extends from about 15 km to about 50 km above the Earth's surface. This layer is characterized by a relatively constant temperature and is mostly composed of nitrogen and oxygen molecules.
The ozone layer protects the Earth from harmful ultraviolet radiation from the sun. Because ozone is lighter than the air below it, it remains in the stratosphere, while the heavier gases in the air below do not reach that high. This chemical stratification is maintained by the balance of ozone production and destruction processes in the stratosphere.
Hence, the stratosphere is the most chemically stratified layer in the atmosphere.
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You have 20.0 G of sodium you want to Nixes sodium with chlorine to create the salt NaCl using percent composition determine what mass of chlorine you need to create the maximum possible amount of NaCl
The mass of chlorine needed to create the maximum amount of NaCl would be, Chlorine mass =41.56 g Cl x 33.2% = 13.7 g Cl.
How determine the mass of chlorine?To determine the mass of chlorine needed to create the maximum possible amount of NaCl, we must first look at the percent composition of sodium chloride. Sodium chloride is composed of 58.44% Na and 41.56% Cl. This means that for every 100 grams of sodium chloride, 58.44 grams is sodium and 41.56 grams is chlorine. Since we have 20.0 g of sodium, we can calculate the amount of chlorine needed to create the maximum amount of sodium chloride. First, convert 20.0 g of sodium to a percentage: 20.0 g of sodium is 33.2% of 58.44%. Then, multiply 41.56 grams of chlorine by 33.2%: 41.56 g Cl x 33.2% = 13.7 g Cl. Therefore, the maximum amount of sodium chloride that can be created from 20.0 g of sodium and 13.7 g of chlorine is 34.1 g. To create this amount of sodium chloride, we need 20.0 g of sodium and 13.7 g of chlorine.To learn more about mass of chlorine refer :
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The mass of chlorine needed to create the maximum amount of NaCl would be, Chlorine mass =41.56 g Cl x 33.2% = 13.7 g Cl.
How determine the mass of chlorine?To determine the mass of chlorine needed to create the maximum possible amount of NaCl, we must first look at the percent composition of sodium chloride.
Sodium chloride is composed of 58.44% Na and 41.56% Cl. This means that for every 100 grams of sodium chloride, 58.44 grams is sodium and 41.56 grams is chlorine.
Since we have 20.0 g of sodium, we can calculate the amount of chlorine needed to create the maximum amount of sodium chloride.
First, convert 20.0 g of sodium to a percentage: 20.0 g of sodium is 33.2% of 58.44%. Then, multiply 41.56 grams of chlorine by 33.2%: 41.56 g Cl x 33.2% = 13.7 g Cl.
Therefore, the maximum amount of sodium chloride that can be created from 20.0 g of sodium and 13.7 g of chlorine is 34.1 g.
To create this amount of sodium chloride, we need 20.0 g of sodium and 13.7 g of chlorine.
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why do you think land is considered a resource
Answer:
Land is considered as an important resource as it provides habitation to a wide variety of flora and fauna. It is also used by human beings for various purposes such as agriculture, forestry, mining, building houses and roads, and setting up industries.
acid rain is the result of pollutants being released into the____
The acid rain is the result of pollutants being released into the atmosphere.
What is acid rain ?
Nitric and sulfuric acids, which are included in acid rain and other dry, abrasive particles that fall to the ground, can harm the surfaces of sculptures, buildings, and other man-made structures. Metal is corroded by the acidic particles, which also hasten the aging of stone and paint.
What is pollutants ?
A material that is present in concentrations that could be harmful to creatures (including people, animals, and plants) or go beyond the limits of acceptable environmental quality is referred to as a pollutant. Frequently, the words "term" and "contaminant" are used interchangeably.
Therefore, acid rain is the result of pollutants being released into the atmosphere.
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the point at which the perpendicular bisectors intersect in a triangle
The point at which the perpendicular bisectors of the sides of a triangle intersect is called the circumcenter of the triangle.
What is a circumcenter?
The circumcenter of a triangle is the point where the perpendicular bisectors of the sides of the triangle intersect. It is the center of the circumcircle, which is the circle that passes through all three vertices of the triangle.
The circumcenter is equidistant from all three vertices of the triangle and is always inside the triangle. Additionally, it is the intersection of the medians, altitudes, angle bisectors and perpendicular bisectors of the triangle.
The circumcenter can also be found by other methods. It is the intersection of the medians, which are the line segments that connect each vertex of the triangle to the midpoint of the opposite side.
It is also the intersection of the altitudes, which are the line segments that are perpendicular to the sides of the triangle and pass through the opposite vertex. The circumcenter is also the intersection of the angle bisectors, which are the line segments that bisect the angles of the triangle and pass through the vertex of the triangle.
Hence, the point at which the perpendicular bisectors of the sides of a triangle intersect is called the circumcenter of the triangle.
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PRACTICE Problems
Predict whether the following single-replacement reactions will occur. If a reaction occurs,
write a balanced equation for the reaction.
21. K(s) + ZnCl₂(aq) →→→
Single-replacement reactions will occur if the reaction below occurs
K(s) + ZnCl₂(aq) →→→ KCl₂ + Zn.
What is Single-replacement reaction?This is also referred to as single displacement reaction and it is referred to as a reaction in which one element is substituted for another element in a chemical reaction.
Single-replacement reactions will occur in the reaction below because it follows and obeys this condition which is:
A + BX ⇒ B + AX
K(s) + ZnCl₂(aq) →→→ KCl₂ + Zn.
Here we can deduce that zinc was substituted which is therefore the reason why it was chosen as the correct choice in this scenario.
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when hydrogen bonds form between water molecules, water____
When hydrogen bonds develop between the molecules, the boiling point of water rises. Hydrogen bonds are created when the electronegative oxygen atoms of two different water molecules combine.
Has a hydrogen atom that it can attach to in a separate water molecule. The molecules are hence strongly attracted to one another. In order to make a hydrogen bond, two atoms from either the same or a distinct molecule are required. Hydrogen bonds can form in two different ways: Between-molecule H-bonding molecules form hydrogen bonds. Hydrogen bonding is possible when the hydrogen atom in a molecule is attached to a strongly electronegative atom. One hydrogen atom in water is wedged between two oxygen atoms, creating a solid bond with the following water molecule.
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Explain how two species can indirectly compete for the same resource even when they never come in contact with one another. Describe an example to show direct competition.
Two species can indirectly compete for the same resource even when they never come in contact with one another if they depend on the same resource but at different times.
An example of indirect competition is for example where two insect feeds on a certain plant during the day and another species feeds on the same plant during the night.
What is indirect competition?Indirect competition occurs when animals that use the same resource don't necessarily interact with one another, such as cheetahs that are active during the day and leopards that are active at night that shares a watering hole in a grassland savanna.
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what is the total combined mass of carbon dioxide and water that is produced?
An automobile gasoline tank contains 20kg of gasoline. And when the gasoline burns, as result, 86kg of oxygen is consumed and water and carbon dioxide are produced. This yields the total combined mass to be produced of carbon dioxide and water is 106kg.
According to the law of mass conservation, the mass of products is equal to the mass of reagents, hence the total aggregated mass of carbon dioxide and water is equal to the total aggregated mass of gasoline and
oxygen.
Numerically it can be represered as 20 kg + 86 kg = 106 kg
Hence, the total combined mass of carbon dioxide and water to be produced is 106kg.
"
Complete question is
An automobile gasoline tank holds 20kg of gasoline. When the gasoline burns, 86kg of oxygen is consumed and carbon dioxide and water are produced.
What is the total combined mass of carbon dioxide and water that is produced?
"
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____are small subunits, that when combined, form polymers.
Answer: Monomers are small subunits, that when combined, form polymers.
Explanation: I hope this helps!
What is the average speed of a bicyclist who rides 75 km in 2.5 hours? please show how you worked it out if you can bc my teacher is very specific
Answer:
30
Explanation:
I’m pretty sure it is
How many molecules are present in 10 grams?.
The number of molecules present in 10 grams of a substance depends on the molar mass of the substance.
The molar mass is the mass of one mole of a substance (6.022 x 10²³) of its molecules. To determine the number of molecules present in 10 grams, we can use the formula:
Number of moles = mass/molar mass Number of molecules
= Number of moles x Avogadro's number (6.022 x 10²³)
For example, if the substance is water, its molar mass is 18.015 grams per mole, and 10 grams of water would contain:
Number of moles = 10/18.015 = 0.5556 moles
Number of molecules = 0.5556 x 6.022 x 10²³ = 3.33 x 10²²
It's important to note that Avogadro's number, which is the number of atoms, ions, or molecules in one mole of a substance, is a physical constant and is the same for all substances. So, the number of molecules present in 10 grams of a substance can be calculated by dividing the mass of the substance by its molar mass and then multiplying it by Avogadro's number.
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What is the percent yield if 18 grams of water are produced when 4 grams of hydrogen with excess oxygen?
To calculate the percentage yield of a reaction, you need to know the theoretical yield (the maximum amount of product that can be produced based on the stoichiometry of the reactants) and the actual yield (the amount of product that is actually produced in the reaction).
The balanced equation for the combustion of hydrogen gas (H2) with oxygen gas (O2) to form water vapour (H2O) is:
2H2 + O2 -> 2H2O
From the balanced equation, we can see that for every 2 moles of H2, 1 mole of H2O is produced. To convert 4 grams of H2 to moles, we use the molar mass of H2 which is 2.016 g/mol.
4g / 2.016 g/mol = 1.98 moles
Now we can calculate the theoretical yield of H2O. Since 2 moles of H2O are produced for every 2 moles of H2, the theoretical yield of H2O is:
1.98 moles x (2 moles H2O / 2 moles H2) = 1.98 moles
The molar mass of H2O is 18.02 g/mol, we can convert the theoretical yield of H2O from moles to grams:
1.98 moles x 18.02 g/mol = 35.7 g
To calculate the percentage yield, we divide the actual yield (18 g) by the theoretical yield (35.7 g) and multiply by 100:
(18 g / 35.7 g) x 100 = 50.5 %
Therefore, the percentage yield of the reaction is 50.5%.
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the quantity of energy released or absorbed as heat during a chemical reaction is called the
The heat content of a system under constant pressure is expressed as enthalpy (H). Chemists monitor variations in enthalpy of chemical systems when reactants are transformed into products regular basis.
At constant pressure, the heat absorbed or released by a process is the same as the enthalpy change and is denoted by the symbol H. The energy collected and emitted in many chemical processes is in the form of heat. An exothermic reaction is a chemical process that produces heat. An endothermic reaction is a chemical process in which heat is absorbed. Exothermic and endothermic processes collaborate to provide energy. The heat content of a system under constant pressure is expressed as enthalpy (H). Chemists monitor variations in enthalpy of chemical systems when reactants are transformed into products on a regular basis. At constant pressure, the heat absorbed or released by a process is the same as the enthalpy change and is denoted by the symbol H. When a reaction occurs, the components absorb or release energy as heat.
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What is the kinetic energy of a 750 kg car moving at 50. 0 km h?.
The kinetic energy of a 750 kg car moving at 50.0 km h is 72300 joules.
The capacity of an object to perform work is called energy, and like work, energy has a unit called the joule (J). Although energy can take many various forms, kinetic energy is the one that comes to mind when we talk about it. Since it is used to describe moving objects, kinetic energy is frequently conceived of as the energy of motion.
mass of car (m)= 750 kg
speed of car (v)= 50 km/h
= 50 x 5/18
= 13.9 m/s
we know that kinetic energy= 1/2 x m x v²
= 1/2 x 750 x 13.9²
= 72300 joules
so the kinetic energy is 72300 joules.
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How many significant figures does the number 1.006 x 10⁷ have?
A) 3
B) 4
C) 5
D) 6
E) 8
Number one question the answer is 4
how are beach sands and grains of salt related to the atom?
Answer:
They both contain atom, sand would be a silicon dioxide molecule. Salt contain sodium chloride.
Explanation:
Both beach sands and grains of salt are composed of atoms and molecules, representing the fundamental building blocks of matter.
Beach sands and grains of salt are both composed of countless tiny particles called atoms and molecules. Atoms are the basic units of matter, consisting of a nucleus of protons and neutrons, surrounded by electrons. Molecules are formed when atoms bond together.
In the case of beach sands, they primarily consist of mineral grains like quartz, each composed of silicon and oxygen atoms bonded together in a crystalline structure. Grains of salt, on the other hand, are made up of sodium (Na) and chlorine (Cl) atoms bonded as sodium chloride (NaCl) molecules.
The relationship between beach sands, salt grains, and atoms lies in their shared composition and arrangement of these fundamental particles, highlighting the underlying unity of matter at the atomic and molecular level.
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A sealed container can hold
6.28 L CO2 at 1.00 atm and 293 K.
How many moles of CO2 fill the
container?
Answer:
0. 261
Explanation:
Use ideal gas formula: PV = nRT, meaning that constant R = [tex]0.08206\frac{(L)(atm)}{(K)(mol)}[/tex]
[tex](1 atm)(6.28L) = n(0.08206\frac{(L)(atm)}{(K)(mol)})(293 K) \\n = \frac{(1 atm)(6.28L)}{(0.08206\frac{(L)(atm)}{(K)(mol)})(293 K)} \\n = 0.26119...\\n = 0.261[/tex]
How high is a 0. 5 kg squirrel sitting if it has 36 J of energy?.
The squirrel is sitting at a height of 7.35 m.
The height squirrel sitting can be calculated as follows:Potential energy is the energy that a body possesses as a result of its position.
The squirrel's potential energy E is given by, if the squirrel has mass m and is at height h.
E=mgh
here, g is the acceleration due to gravity.
m = 0.5 kg; E=36 J
Take the acceleration caused by gravity as an example.
g= 9.8 m/s²
Rewrite the energy equation in terms of h.
h= E/ mg
Substitute the given values and calculate the value of h.
h= E/mg
h= 36J/(0.5 kg x9.8 m/s)
h = 7.35 m
The squirrel is at a height of 7.35 m
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Rearrange the work equation and show the equation for force.
Work equation: W=Fxd
Answer:
Force=Work done÷ distance travelled
Explanation:
To do this, you want to make the Force variable on its own so you divide d on both sides to get F=W/d
Hope this helps.
n physical changes, substances might change in ________ but not in ________.
Answer: Physical properties, but not in its identity
Explanation:
Physical changes only change the substances physical properties, not the substance’s identity
how are q and w related during this isothermal expansion?
According to the First Law of Thermodynamics ΔU = Q + W in IUPAC convention, it follows that Q = −W for the isothermal expansion or compression of an ideal gas.
In thermodynamics, an isothermal process is one of the types of thermodynamic processes, in which the temperature (T) of a system remains constant, i.e. ΔT = 0. This, in a typical manner, occurs when a system is in direct contact with an outside thermal reservoir, and a change in this system occurs slowly enough to allow the system to be continuously and gradually adjusted to the temperature of the reservoir through heat exchange.
When the vacuum gets expanded in an isothermal expansion, it leads to the free expansion of a gas. In the case of an ideal gas, the rate of free expansion is NIL (0), that implies that the work done is 0. The value of 0 is the result regardless of whether the isothermal expansion process is irreversible or reversible.
Some of the examples of reversible cases of isothermal process include converting ice from its solid-state to the liquid-state of water, hydrogenation and dehydrogenation in milling a chemical, etc.
Examples for an irreversible condition of an isothermal process include work that is done against the friction, , magnetic hysteresis, Joule’s heating effect, etc.
The relation between Q and W during an isothermal expansion process is: Q = -W
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