The total heat that is required to produce the solid is obtained as 34.8 kJ.
What is the energy required?We know that the energy of the substance can be defined as the ability to do work. In this case, energy has been supplied to the system as the heat that is supplied to the substances.
There are stages that the objects would have to go through and in all these stages we have heat that is evolved or absorbed.
As the object cools from 120.9 °C to 87.9 °C
H = mcdT
m = mass of the object
c = specific heat capacity
dT = temperature change
H = 221.6 g * 1.5 J/g·°C * (87.9 °C - 120.9 °C)
H = -10,969 J or 10.969 kJ
As it is converted from gas to liquid;
H = 221.6 g/75 g/mol * 34.6 kJ/mol
H = 2.95 mol * 34.6 kJ/mol
H = 102.1 kJ
As the liquid cools from 87.9 °C to -30.9 °C
H = 221.6 g * 2.4 J/g·°C * ( -30.9 °C - 87.9 °C)
H = -63.2 kJ
As the liquid changes to solid;
H = 221.6 g/75 g/mol * 6.3 kJ/mol
H = 2.95 mol * 6.3 kJ/mol
H = 18.6 kJ
As the solid cools further to -61.9°C
H = 221.6 g * 4.9 J/g·°C * (-61.9°C - (-30.9 °C))
H = -33.7 kJ
Total heat involved;
10.969 kJ + 102.1 kJ - 63.2 kJ + 18.6 kJ - 33.7 kJ
= 34.8 kJ
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H2(g)+O2(g)→H2O(l) Express your answer as a chemical equation. Identify all of the phases in your answer.
Phases in the given chemical reaction:
Hydrogen H₂ is in gas (g) phase
Oxygen O₂ is in gas (g) phase.
Water H₂O is in liquid (l) phase.
What is a phase?A phase in thermodynamics that is a chemically and physically homogeneous or homogeneous amount of substance that can be mechanically separated from a heterogeneous mixture and that can consist of a single substance or a mixture of substances. The three basic phases of matter are solid, liquid, and gaseous (vapor), but others are believed to exist, including crystalline, colloidal, glassy, amorphous, and plasma phases. A phase change is said to have occurred when a phase changes from one form to another.
For the given reaction,
H₂(g) + O₂(g) → H₂O(l)
Hydrogen and oxygen are present in gaseous phase, while water is in liquid phase.
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3. A solution contains 0.42 moles of solute in 0.75 L. Calculate the molarity of the solution.
0.56 is the molarity of a solution.
Molarity (M): It is defined as the number of moles of solute per liter of solution, and it is one of the most common units used for the purpose of measuring the concentration of a solution.
To calculate molarity we have three steps:
To Find the number of moles of solute which dissolved in the solution,Find the volume of solution in liters.Later, Divide the moles of solute by liters of solution.To define the molarity of the solution we have a small formula:
Molarity=moles/Liters-----(1)
Given that
m=0.42
L=0.75
By, substituting the m and L values in equation(1) we get:
Molarity=0.42moles of solution/0.75 L of solution
Molarity=0.56M
Hence, The molarity of this solution is 0.56 M (moles per liter).
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What is the volume of a bar of soap that has a density of 2.5 g/cm3 and a mass of 100 g?
O4 cm3
O 0.4 cm3
O 400 cm3
O 40 cm3
The volume of a bar of soap that has a density of 2.5 g/cm3 and a mass of 100 g is 40 cm ³. Therefore, option D is correct.
What is density ?The mass of a substance per unit of volume is its density. A mechanically accepted measure is density. Density is most frequently represented by the symbol, however the Latin letter D may also be used.
The mass of a solid substance's unit volume. d = M/V, where d is density, M is mass, and V is volume, is the formula for density. Grams per cubic centimeter are a typical unit of measurement for density.
Density = m / V
volume = mass / density
= 100 / 2.5
= 40 cm³
Thus, option D is correct.
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Pls, help I don't get it Compare and contrast Marine and freshwater ecosystems
The saltwater of the ocean creates the marine ecosystem. Freshwater bodies of water, such as lakes, ponds, streams, and rivers, make up the freshwater ecosystem.
What are ecosystems?
All the organisms and the physical setting they interact with make up an ecosystem. The nutrition cycles and energy flows connect these biotic and abiotic elements.
The marine biome, which makes up around 70% of the planet's surface, is the largest biome. On Earth, freshwater biomes make up about 20% of the land. The salt content distinguishes the two. They both have several aquatic animal species.
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Which atom ha the electron configuration 12 2 2 2p 6 3 2 3p 6 4 2 3d 10 4p 6 5 2 4d 2 ? Why?
The element Zirconium has the given electronic configurations because its atomic number is 40 and its electrons are present in d subshell since it is a d block element.
Zr (Zirconium) is an element with atomic number 40 in the periodic table located in the V (fifth) period having melting point 1852 ℃. and density: 6.51 g/cm³. Electronic configuration of Zirconium atom in ascending order of orbital energies:
1s² 2s² p⁶ 3s² p⁶ d¹⁰ 4s² p⁶ 5s² 4d²
The electronic configuration of the Zirconium atom in the ascending order of the levels:
1s² 2s² p⁶ 3s² p⁶ d¹⁰ 4s²p⁶d² 5s²
The reduced electronic configuration of Zr:
[Kr] 4d² 5s²
Therefore Zirconium atom is the element having given electronic configuration
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liquid water at 50 °c is heated to steam at 150 °c. which piece of information is not required to determine the amount of heat that must be added for this change to occur?
ΔH(fusion) is not required to determine the amount of heat that must be added for this change to occur.
What is specific heat and enthalpy of phase transition?
The energy required in the form of heat to increase temperature by one-degree Celsius and enthalpy of phase transition defined as heat change at constant pressure and temperature for per mole substance from one phase to another.
In between 50 to 100 °C water remains in same phase it gains heat so calculate it using specific heat of liquid.
b) At 100°C it absorbs heat and transfer into vapor phase and require ΔH(vaporization).
c) In between 100°C to 150°C in vapor phase specific heat of gas is required.
But no requirement of ΔH (fusion).
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PLS HELP URGENT
13)
Calculate the atomic mass of C by using the data from carbon isotopes.
The abundance of 12C is 98.93%. 13C is another naturally occurring isotope. What is the percent abundance of 13C?
The mass of 13C is 13.003 amu. Multiply the mass of 13C by its abundance. Report the number to 3 significant digits.
The mass of 12C is 12.000 amu. Multiply the mass of 12C by its abundance. Report the number to 5 significant digits.
Add the last two numbers together to get the atomic mass of carbon. Report the number to 5 significant digits.
Explanation:
Actually the total abundant of isotopes of any element in the world must sum up to 100 percent. So we initially know that 12c is 98.9 percent. Therefore the remaining of the remains of 100 must be 12
3c = 100%- 98.9
13c= 1.1%
what is the systematic iupac name of the compound below? multiple choice 6-bromo-4-ethylbenzenecarboxylic acid 2-bromo-4-ethylbenzenecarboxylic acid ortho-bromo-para-ethylbenzoic acid 1-bromo-3-ethylbenzoic acid
B. 2-bromo-4-ethyl benzene carboxylic acid. The term "industrial chemical" is short form for "International Union of Pure and Applied Chemistry(iupac).
What are IUPAC guidelines?The IUPAC nomenclature is based on naming the longest continuous or ring-shaped chain of carbon atoms linked by a single bond within a given molecule. Prefixes or suffixes are used in accordance with a predetermined order to identify all deviations, including those involving multiple bonds or atoms other than carbon and hydrogen.
The IUPAC name is it alphabetical?The base name is written first, then the name of the compound is spelt out in alphabetical order (derived from the number of carbons in the parent chain). The name has no spaces in it.
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What is the formula for cobalt(II) nitride?
Answer:
Co(NO3)2
Explanation:
The chemical formula for cobalt(II) nitride is Co₃N₂ which has 3 and 2 cobalt and nitrogen atoms respectively.
What is chemical formula?Chemical formula is a way of representing the number of atoms present in a compound or molecule.It is written with the help of symbols of elements. It also makes use of brackets and subscripts.
Subscripts are used to denote number of atoms of each element and brackets indicate presence of group of atoms. Chemical formula does not contain words. Chemical formula in the simplest form is called empirical formula.
It is not the same as structural formula and does not have any information regarding structure.It does not provide any information regarding structure of molecule as obtained in structural formula.
There are four types of chemical formula:
1)empirical formula
2) structural formula
3)condensed formula
4)molecular formula
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in a experiment similar to yours, a solution is prepared by adding 4.512 g of slaked lime also known as calcium hydroxide to 500.00 ml of water. a. what is the molarity of the solution
0.1218 M is the molarity of the solution
mole of Ca(oH)2 == mass/ molar mass
= 4.152/74.053
=0.060 g. mol
volume of the solution= 500ml
=500/1000
= 0.5 L
Molarity= mole/ litre
= 0.060 g mol/ 0.5L
= o.1218 M
The amount of a solute per unit volume of solution is how much a chemical entity is present in a solution, and this is known as its molar concentration. "The molarity of products is divided by the molarity of reactants" is the formula for determining an equilibrium constant.
in a experiment similar to yours, a solution is prepared by adding 4.512 g of slaked lime also known as calcium hydroxide to 500.00 ml of water. a. what is the molarity of the solution
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Thermometers in the past were filled with mercury but most are now filled with alcohol instead due to safety reasons. Why do you think alcohol is used instead of water?.
There are some thermometers that use alcohol instead of the mercury that is typically used. Alcohol has a lower freezing point (-114°C) than water (0°C), which is why we use it instead of water.
On the glass capillary tube, alcohol's vivid colour makes it simple to see.
Alcohol thermometer contents are less harmful and will evaporate more quickly than mercury in glass thermometer contents. The most popular variant is made of ethanol since it is inexpensive and has only a minimal risk of spillage.
What is thermometer?
A thermometer is a device used to gauge temperature. It can gauge the temperature of a solid substance like food, a liquid substance like water, or a gas substance like air. Celsius, Fahrenheit, and kelvin are the three most widely used units for measuring temperature.
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Whenever Ayan returns from school he empties his water bottle in the potted plant instead
of throwing it in the sink. He always says his housemaid to use the water for watering plants
in the garden after mopping the house.
(a) Can you suggest any other use of the water left after mopping?
(b) What is the function of water in plants?
(c) What values of Ayan is shown here?
Drip irrigation is the ideal irrigation system for use with vegetable gardens, flowers, trees, and other watering needs. A drip irrigation system for gardens helps you save time, money, and water.
What potted plant instead of throwing it in the sink?In those pots lacking drainage holes, a layer of stones is used as a form of drainage layer. By using this method, surplus water might go from the soil and, consequently, the roots of your plant, into the area with the pebbles.
A drip system that has been set up correctly will operate automatically at a certain time of day for a specific duration.
Therefore, a) use the water to wash the car. b) Often used for transpiration to create a suction force, creating a transpiration pull. c) Ayan values water, conserving it and giving the most efficient and optimum function.
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Jack can drink a bottle of cider in 6 days. Jill can drink a bottle of cider in 12 days.
The combined rate when Jack and Jill drink together at their respective speeds ,the bottle of cider will finish in 4 days.
A rate in mathematics is indeed the ratio of two related elements stated in different units.The numerator of the ratio indicates the equivalent rate of increase in the other (dependent) variable if the denominator is given as a single entity of one of these values and it is expected that this number may well be changed consistently (i.e., is an output factor).
Jill drinks in one day= 1/12 bottle
Jack consumes 1/6 bottle in a day.
Together they will drink = 1/12+1/6 = 3/12 = 1/4 bottle
"Per unit of time" is a prevalent rate unit that includes ideas like speed, heart rate, and flux.Electric field ratios, exchange rates, and literacy rates are non-time denominators Hence Jack and Jill will completely drink the bottle in 4 days .
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periodic scavenger hunt what color element symbol designates elements that are a gas at a given temperature
Red color element symbols indicate elements that are gases at a specific temperature in periodic scavenger hunts.
What exactly is an element?An element is a basic substance that is hard to break down into smaller pieces. In chemistry and physics, an element is anything that cannot be further separated by non-nuclear processes. In computers and mathematics, an element is a discrete part of a larger structure or collection.
What does element mean?Any compound that cannot be broken down into simpler chemicals by regular chemical processes is referred to as a chemical element or element. The building blocks from which every matter is made are called elements.
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What type of nuclear reaction occurs in the Sun?
Hello,
I hope you and your family are doing well!
The nuclear reactions that occur in the Sun are fusion reactions.
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Happy Holidays!
Lipids, proteins, carbs... What's the difference?
Lipids are more of a fatty, oily, and waxy substance that serve as long-term energy for whenever the body may need it. You can find lipids in oily foods such as salad dressing, olives, avocados, peanut butter, nuts, seeds, and some fish.
Proteins are enzymes that are used to strengthen and keep the body functioning. Proteins make up our bones, hair, skin, nails, and muscle, and without them our bodies wouldn't be strong enough to function or carry out even the simplest of tasks. Proteins are found in more animal-based foods such as meat, vegetables, grains, and seeds.
Carbohydrates are more of the sugary molecules that provide short-term or immediate energy for the body. They can be found in foods like bread, beans, milk, popcorn, potatoes, cookies, spaghetti, and soft drinks.
Consider a general reaction
A(aq)⥫enzyme⥬B(aq)
The Δ°′ of the reaction is −9.660 kJ·mol−1 . Calculate the equilibrium constant for the reaction at 25 °C.
What is Δ for the reaction at body temperature (37.0 °C) if the concentration of A is 1.6 M and the concentration of B is 0.50 M ?
The equilibrium constant for the reaction at 25 °C is 1.3602 . The reaction at body temperature (37.0 °C) if the concentration of A is 1.6 M and the concentration of B is 0.50 M is - 87.287 kJ / mole.
What is equilibrium constant ?Equilibrium constant is defined as a number that illustrates the relationship between the quantities of reactants and products in an equilibrium chemical reaction at a specific temperature.
ΔG° = - 9.660 kJ / mole = 9.660 x 10 ³ J / mole
T = 25 + 273.15 = 298.15 K
ΔG° = - RT ln K
ln K = -ΔG° / RT
ln K = - ( - 9.660 x 10 ³ J / mole ) / 8.314 J / k . mole X 298.15 K
ln K = 3.8970
K = 1.3602
T = 37 + 298.15 = 310.15 K
ΔG = ΔG° + RT ln Q
Where Q = 0.55 / 1.6 = 0.34375
ΔG = -9.660 X 10³ + [ 8.314 x 310.15 x ln ( 0.34375 )]
ΔG = - 87287.34 J / mole
ΔG = - 87.287 kJ / mole
Thus, the equilibrium constant for the reaction at 25 °C is 1.3602 . The reaction at body temperature (37.0 °C) if the concentration of A is 1.6 M and the concentration of B is 0.50 M is - 87.287 kJ / mole.
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hydrogen gas was collected in a burette in a water bath with a water height difference of 15.0 cm. please calculate the pressure in the burette if the atmospheric pressure in the room at that time was 765.0 torr.
The pressure in the burette if the atmospheric pressure in the room at that time was 765.0 torr is 717.44 torr.
Calculation:-
We know that density of water = 1g/mL
Given : Density of mercury = 13.6 g / mL
Also, 1 torr = 1mmHg
So 1 torr = 13.6 mm of H2O
So 1mm of water = 1/13.6 torr
Height of water given = 14.1 cm = 141 mm
so 14.1 cm = 141 / 13.6 torr = 10.36 torr
Atmospheric pressure = 753 torr
Therefore pressure of H2 and pressure of water column = 753 torr
Hence pressure of hydrogen = 753 - 10.36 = 742.64 torr
A further correction needs to be made because the H2 gas also contains water vapor.
We know from standard values that vapour pressure exerted by water at 26 0C = 25.2 Torr
So pressure of dry hydrogen = Pressure of hydrogen - pressure of vapours = 742.64 - 25.2 = 717.44 torr
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An ion has an atomic number of 13, a mass number of 27, and 10 electrons. How many neutrons does the nucleus of the ion have?
14
13
3
27
Answer:
[tex]\huge\boxed{\sf 14}[/tex]
Explanation:
Atomic number = 13
Mass number = 27
No. of neutrons:= Mass number - Atomic number
= 27 - 13
= 14[tex]\rule[225]{225}{2}[/tex]
if you mix 2.8 ml of 2.000 m fe3 with 2.8 ml of 0.000815 m scn-, what is the concentration of fescn2 at equilibrium?
In an experiment comparable to the one you conducted in the lab, it was discovered that the [Fe(SCN)2+] equilibrium concentration in a solution created by combining 7.0 mL was 2.510-5 M. The concentration of [Fe(SCN)]2+ is 2 104 M at equilibrium.
What is equilibrium constant's ?
The equilibrium constant's value. Fe is an excess reactant, whereas SCN is the limiting reactant. The reason for creating this reactant in excess is because, according to Le Chatelier's principle, this excess will cause the reaction to shift to the products side, causing the reaction to produce as much Fe(SCN) as possible.
As a result, the concentration of FeSCN2+ in the equilibrium mixture is roughly equal to the SCN- concentration that existed prior to the reaction.
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This question has two parts
(I recommend you answer in CER Strategy to help me earn extra points.)
(I need you help ASAP!)
(Use data and text as evidence)
Text:
In animal populations, genes help determine when organism will breed during the year. Scientists have observe that the distribution of the time of year breeding genes in animal populations has been changing as average global temperatures increase. Red squirrels in Canada are one example of a population that has shown a shift in the frequency of certain genes. Scientists have observed the genes related to breeding earlier in the spring increasing in red squirrel populations. The chart shown below provide some information about red squirrels.
The data about red squirrels:
- Red squirrels frequently produce once a year
- Mating season is spring
- Red squirrels don't hibernate, but they store food for winter because food is less available
- Their diet is mostly herbivorus; sometimes eat insects, eggs, small birds/mammals
Part A: Describe ONE survival advantage for red squirrels to breed earlier in the spring.
Part B: Identify and explain the mechanism by which the gene for breeding earlier in the spring can increase in the red squirrel population over time.
Answer:
Part A: One survival advantage for red squirrels to breed earlier in the spring is that they may be able to take advantage of an earlier availability of food resources. As the climate warms and average temperatures increase, plants may begin to grow and produce food earlier in the year. By breeding earlier in the spring, red squirrels may be able to access these food resources before they become scarce, which could improve the survival and reproductive success of their offspring.
Part B: The mechanism by which the gene for breeding earlier in the spring can increase in the red squirrel population over time is natural selection. Natural selection is the process by which certain traits become more or less common in a population based on their impact on an individual's ability to survive and reproduce. If red squirrels that breed earlier in the spring are more successful at surviving and reproducing than those that breed later, then the genes for early breeding will become more common in the population over time. This process can occur over many generations, leading to a shift in the distribution of the time of year breeding genes in the population.
Oil used to lubricate automobile engines is not biodegradable. What is the BEST way of disposing of this used oil?
A.
use it to paint a wooden fence to make it water repellant
B.
put it on the weeds in a park to kill the weeds
C.
take it to the local automotive parts store to be recycled
D.
pour it down the drain so it can go to the water recycling plant
Answer:
it is C. take it to the local automotive parts store to be recycled
Explanation:
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how many electrons are gained in a balanced half-reaction in which chlorine gas is reduced to the aqueous chloride ion?
Each chlorine atom acquires an electron during the reaction to create a chloride ion (Cl-), which is the process known as reduction.
What is an example of a redox reaction?A redox reaction is when there is simultaneous oxidation and reduction. CuO+H2→Cu+H2O. Example: In this process, hydrogen is oxidized to water while copper oxide is reduced to copper.
Combination, breakdown, displacement, combustion, and disproportionation are the five primary categories of redox processes.
The definition was eventually expanded to cover additional processes in which electrons are lost, regardless of whether oxygen was present, because it was understood that the material loses electrons when it is oxidized.
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the famous gold foil experiment proved that the nucleus an atom negatively charged and has a low density true or false
Answer:
false, Rutherford's experiment proved the nucleus being positive and dense.
Which of the following is not true about the volume of a gas? O Generally, the volume can be easily changed. O Most of the volume is empty space. O The volume is occupied by particles in continuous, rapid, random motion. O The volume is about 10 times greater than that occupied by an equal number of particles in the liquid or solid state.
Answer:
O The volume is about 10 times greater than that occupied by an equal number of particles in the liquid or solid state.
what is the reaction between phosphate ion (PO4 3-) and hydronium ion (H3O+)
Answer:
H3O+(aq) + PO43−(aq) ⇌ HPO42−(aq) + H2O(l)
Notice that the total charge (2-) is the same on both sides of the equation, and that this is reaction can take place in both directions.
Explanation:
i hope it helps uh..!!mark me as brainliest ♥️what is the bond order for a second-period diatomic particle containing seven electrons in antibonding molecular orbitals and eight electrons in bonding molecular orbitals?
The Bond Order would be 0.5.
Bond order is the number of bonding pairs of electrons between two atoms. In a covalent bond between two atoms, a single bond has a bond order of one, a double bond has a bond order of two, a triple bond has a bond order of three, and so on.
Bond Order= [tex]\frac{Bonding E- Antibonding E}{2}[/tex]
so ,
= [tex]\frac{8-7}{2}[/tex]
= 0.5
As Bond Order is 0.5 so molecule would be very reactive as bond is pretty weak.
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What type of heat transfer happens
Answer:
Explanation:
14. radiation
15. thermal conductivity
16. conduction
17. convection
three moles of a monatomic ideal gas undergoes an isochoric process in which the temperature changes from 500 k to 300 k. calculate the change in volume during this process (in m3).
Change in volume is 0 m3 when three moles of a monatomic ideal gas undergoes an isochoric process in which the temperature changes from 500 k to 300 k.
An isochoric process, also known as a constant-volume process, isovolumetric process, or isometric process in thermodynamics, is a thermodynamic process where the volume of the closed system having undergone such a method remains constant.
In everyday life, we see an isochoric process once we boil the water in a pressure cooker. Because the temperature increase is accomplished at a constant volume, we encounter an isovolumetric process when we transfer heat to the container.
In this problem we have T1=500K T2=300K
Since in isochoric process volume in constant, change in volume = 0
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Lead (atomic radiu = 0. 181 nm) crytallize with a face-centered cubic unit cell. What i the length of a ide of the cell?
The length of the side of the cell is 0.511nm when lead crystallizes with a face-centred cubic (fcc) unit cell.
What do you mean by crystallizes?
Having a distinct shape, a crystal is solid. When the symmetrically aligned smooth plane surfaces of crystals collide, sharp edges are created. After cooling a heated saturated solution, crystals can be formed. Crystallization is the name given to this procedure.
What is Face-centered cubic?
A face-centred cubic unit cell structure is made up of atoms arranged in a cube with six additional whole atoms placed in the centre of each cube face and a fraction of an atom at each of the cube's four corners. Eight additional unit cells share the atoms at the cube's corner.
What are the calculations?
For the fcc unit cell, a=2 √2 r.
Here, a is the edge length and r is the atomic radius (0.181 nm).
a=2 √2 × 0.181 =0.511 nm.
Hence, the length of a side of a cell is 0.511nm.
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