a.
The atomic radius of iridium is 1.355 Å
For a face-centered cubic unit cell, with edge length, a and atomic radius r,
we have a² + a² = (4r)²
2a² = 16r²
r² = a²/8
r = a/√8
Since a = 3.833 Å,
Substituting this into the equation, we have
r = a/√8
r = 3.833 Å/√8
r = 3.833 Å/2.828
r = 1.355 Å
So, the atomic radius of iridium is 1.355 Å
b.
The density of iridium metal is 22.67 g/cm³
To find the density of the iridium metal, we need to find the mass of atoms per unit cell.
So, for the face centered cubic iridium atom, there are 6 faces per unit cell × 1/2 atoms per face + 4 corners per unit cell × 1/4 atoms per corner = 3 atoms + 1 atom = 4 atoms per unit cell.
So, the mass of the atoms in the unit cell is m = number of atoms/cell × number of moles/atom × molar mass of Iridium
= 4 atoms/cell × 1 mol/6.022 × 10²³ atoms × 192.22 g/mol
= 768.88/6.022 × 10²³ g/cell
= 127.68 × 10⁻²³ g/cell
= 1.2768 × 10⁻²¹ g/cell
Next, we need to find the volume of the unit cell which is V = a³
= (3.833 Å)³
= (3.833 × 10⁻¹⁰ m)³
= 56.314 × 10⁻³⁰ m
= 5.6314 × 10⁻²⁹ m
So, the density of iridium = mass of unit cell/volume of unit cell
= m/V
= 1.2768 × 10⁻²¹ g/cell ÷ 5.6314 × 10⁻²⁹ m
= 0.2267 × 10⁸ g/m³
= 0.2267 × 10⁸ g/m³ × 10⁻⁶ m³/cm³
= 0.2267 × 10² g/cm³
= 22.67 g/cm³
So, the density of iridium metal is 22.67 g/cm³
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Which pair of elements are in the same period?Hg & PbLi & NaB & ClO & As
Answer:
Hg Pb are in one, Li and B and O are in one, and NaCl are in one, As is alone
Explanation:
Periods are horizontal
Hope this helps!
A sample of Ammonia gas at 650mmHg and 15 degree has a mass of 56.8g.calculate the volume occupied by the gas. Take N=14, H=1,R=8.3145jk.
Answer:
The first thing we have to do is change and state all the units so that we can use our ideal gas law equation ([tex]PV = nRT[/tex]).
650 mmHg is a pressure unit, we have to convert this to kiloPascals. We know that 760 mmHg gives us 101 kPa.
[tex]650 \ mmHg \ * \ \frac{101kPa}{760 mmHg} = 86 \ kPa[/tex]
P = 86kPa
T = 15°C + 273K = 288K
R (Gas constant) = 8.31 kj/mol
Molar mass of Ammonia ([tex]NH_{3}[/tex]) = (1 x 3) + (14) = 17g/mol
n (moles) = [tex]\frac{mass}{molar \ mass}[/tex] [tex]= \frac{56.8}{17} =[/tex] 3.34 mol
V = ?
Rearrange the equation to solve for Volume:
[tex]V = \frac{nRT}{P}[/tex]
Substitute the values inside:
V = [tex]\frac{(3.34)(8.31)(288)}{(86)} = 93 L (rounded)[/tex]
Therefore 93 L of volume is occupied by the ammonia gas.
Each cart below is pushed across a room with the same amount of force. Which cart will result in the greatest change in speed?
F.A 75 kg cart being pushed with a 200 N force
G.A 125 kg box being pushed with a 200 N force
H.A 350 kg box being pushed with a 200 N force
J.A 450 kg cart being pushed with a 200 N force
The cart with the greatest change in speed is the cart with a mass of 75 Kg
Acceleration is defined as the change in velocity of an object with time. Also, acceleration is related to the force and mass according to the following equation:
Acceleration (a) = Force (F) / mass (m)
a = F / mTo answer the question, we shall determine the acceleration of each cart.
For cart of mass 75 kgMass (m) = 75 KgForce (F) = 200 NAcceleration (a) =?a = F / m
a = 200 / 75
a = 2.67 m/s²For cart of mass 125 kgMass (m) = 125 KgForce (F) = 200 NAcceleration (a) =?a = F / m
a = 200 / 125
a = 1.6 m/s²For cart of mass 350 kgMass (m) = 350 KgForce (F) = 200 NAcceleration (a) =?a = F / m
a = 200 / 350
a = 0.57 m/s²For cart of mass 450 kgMass (m) = 450 KgForce (F) = 200 NAcceleration (a) =?a = F / m
a = 200 / 450
a = 0.44 m/s²From the above illustrations, we can see that the cart with a mass of 75 K has the greatest change in speed (i.e 2.67 m/s²)
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Answer:
D
Explanation:
F. 200-75=125
G. 20-125=75
H. 350-200=150
J. 450-200=250
250 is the biggest number so it has the biggest change
What are 2 substances that will NOT conduct electricity? Plz explain.
Answer:
Covalent compounds (solid liquid solutions)
non-metal elements are insulators but not conductors of electricity.
Explanation:
Metal elements and carbon (graphite) are conductors of electricity
True or false? In giant covalent structures the atoms form strong bonds by sharing electrons.
Answer:
True
Explanation:
its true don't lie on here please
In giant covalent structures such as graphite or diamond, the atoms form strong bonds by sharing electrons. Therefore, the given statement is true.
What is a covalent bond?A covalent bond can be defined as a chemical connection formed by the sharing of electron sets between particles. A covalent bond can be created by the mutual sharing of electrons from both atoms.
The pair of electrons that are shared in this kind of bonding is known as the shared or bonding pair. Covalent bonds are the sharing of bonding pairs of electrons that will provide the stability of the atom in its outer shell.
Elements that have very high ionization energies are incapable of exchanging electrons or elements having low electron affinity cannot accept electrons. Covalent bonding between two non-metallic atoms is characterized by the equal sharing of electrons between the atoms and covalent bonds with an electronegativity difference of participating atoms is more than 2.0.
Therefore, a giant structure like a diamond has strong covalent bonds that require a lot of energy to break.
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4. If 100.0 g of water is cooled from 25.3°C to 16.9°C, what quantity of
energy has been transferred from the water?
Answer:
Dived the numbers by each other
Explanation:
25.3/19.9
What does it mean by solution in salt solution, sugar solution, etc.
Which substances will make a salt when combined?
Vinegar and tea
Soda and wine
Soda and ammonia
Fertilizer and detergent
Answer:
Soda and wine is the answer to your question.
Explanation:
yo make salt you need a base and an acid. in this case the base is soda and the wine is acid. hope that helps :)
which best explains why water dissolves most salts?
Answer:
where are the answers?
Explanation:
hydrogen ions ________ acidity of the water which is a key point.
Answer:
Raise
Explanation:
H+ ions are acidic and lower the PH of water.
Which two elements are found in significant amounts (1% or more) in both the Universe and the human body?
Answer:
hydrogen and helium is the answer.
how many pounds of gold are present in 1 cubic mile of seawater?
Answer:
38 pounds of gold in cubic mile of seawater.
How many moles of CO2 are produced from 15.6 g of NaHCO3?
Answer:
0.185moles
Explanation:
1mole of bicarbonate produces 1mole of CO2
so 0.185 mole produces 0.185 moles of CO2
what is mass of sodium hydroxide NaOH is present in 0.25 mole of sodium hydroxide
pls be quick
Finding molar mass of NaOH
We know that
Molar mass of Sodium (Na) = 23 g/mol
Molar mass of Oxygen (O) = 32 g/mol
Molar mass of Hydrogen (H) = 2 g/mol
So,
Mass of 1 mole of NaOH
=> 1 × 23 + 1 × 16 + 1 × 1
=> 23 + 16 + 1
=> 40 g/mol
Now,
Mass = 40 × 0.25
Mass = 10 g
Which statement concerning simple sugars and amino acids is correct
Answer:
Is there be suppose a file with this?
Explanation:
A nuclear _ is a large chamber where fuel rods are located
The answer is going to be a nuclear reactor
15 points who can solve help plsss now
Answer:
C. Al and O2
Explanation:
The reactants are the elements or compounds that is becoming the result
So Al and O2
Hope this helps!
What are the base units the SI units are based on?
A-10
B-100
C-1,000
D-1
Answer:
A-10
Explanation:
In the SI, designations of multiples and subdivision of any unit may be arrived at by combining with the name of the unit the prefixes deka, hecto, and kilo meaning, respectively, 10, 100, and 1000, and deci, centi, and milli, meaning, respectively, one-tenth, one-hundredth, and one-thousandth.
IM NOT SURE PO
plizzz helpppp
consider the photo
A scientist tested a series of solutions to determine their pH, and recorded the results in this table.
Substance pH
A 9
B 12
C 11
D 14
According to this data, which solution would be most effective at neutralizing a strong acid?
Substance A
Substance B
Substance C
Substance D
Answer:d
Explanation:
CH4+4S-CS2+2H2S
how many moles of CS2 can be formed by the complete reaction of 10.6 mol of S
Let's check the equation
[tex]\\ \sf\longmapsto {CH_4\atop 1mol}+{4S\atop 4moles}\longrightarrow {CS_2\atop 1mol}+{2H_2S\atop 2moles}[/tex]
4moles of S gives 1 mol of CS21mol of S gives 1/4=0.25mol of CS210.6mol of S gives:-[tex]\\ \sf\longmapsto 10.6(0.25)=2.65moles\:of\:CS_2[/tex]
Calculate the energy of a proton of light with a frequency of 8.5x1014 Hz.
Answer:
[tex] \huge{5.632 \times {10}^{ - 19} \: J}[/tex]
Explanation:
The energy of the proton can be found by using the formula
E = hfwhere
E is the energy in J
f is the frequency in Hz
h is the Planck's constant which is
6.626 × 10-³⁴ Js
From the question we have
E = 6.626 × 10-³⁴ × 8.5 × 10¹⁴
We have the final answer as
[tex]5.632 \times {10}^{ - 19} \:J[/tex]
Hope this helps you
7. What is the mass of 389 cm°of propane if the density is 19.3 g/cm?
We are given that–
Volume of Propane is = 389 cm³Density of Propane is = 19.3 g/cm³[tex]\qquad[/tex]________________________
As we know –
[tex]\qquad[/tex][tex] \pink{\bf\longrightarrow {Mass = Volume \times Density } }[/tex]
[tex]\qquad[/tex][tex] \bf\longrightarrow Mass_{(Propane)} = 389 \times 19.3 [/tex]
[tex]\qquad[/tex][tex] \bf\longrightarrow Mass_{(Propane)} = 7507.7 \: g[/tex]
Hence, Mass of Propane is 7507.7 g.[tex]\qquad[/tex]______________________
Mass of a substance is the amount of the constituting particles per unit volume. The mass of the [tex]\bold { 389\ cm^3}[/tex] of propane is 7.507 kg.
Mass of a substance is the amount of the constituting particles per unit volume. It is measured in kilograms (kg).
The formula for mass,
M = v x d
Where,
M - mass
v - volume = [tex]\bold { 389\ cm^3}[/tex]
d - density = 19.3 g/cm
Put the values in the formula,
M = [tex]\bold { 389\ cm^3}[/tex] x 19.3 g/cm
M = 7507.7 g
M = 7.507 kg
Therefore, the mass of the [tex]\bold { 389\ cm^3}[/tex] of propane is 7.507 kg.
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a scientist finds an organism that has a single cell without a nucleus.This organism was found in pond water.In which KINGDOM douse it belong?if you can explain
Archaea (Archaeon ): Single-celled microorganisms without nuclei and with membranes different from all other organisms. Once thought to be bacteria.
Unicellular organism
-A unicellular organism, also known as a single-celled organism, is an organism that consists of a single cell, unlike a multicellular organism that consists of multiple cells. Unicellular organisms fall into two general categories: prokaryotic organisms and eukaryotic organisms.
what type of elements are involved in covalent bonding
Answer:
non-metals
Explanation covalent bonds occur between elements that are far apart on the periodic table.
The types of elements that are significantly involved in covalent bonding are known as non-metals.
What is Covalent bonding?Covalent bonding may be defined as a type of chemical bonding that may involve the mutual sharing of electrons in order to construct electron pairs between atoms of non-metals. These electron pairs which are formed between atoms are known as bonding pairs or shared pairs.
According to the context of this question, covalent bonds are generally formed between nonmetals. While metallic bonds are the type of chemical bonds which are typically formed between the metallic element.
Another type of bonding may also be formed between elements. This type of bonding is known as Ionic bonding. This chemical bonding mat generally arises between metals and non-metals.
Therefore, the types of elements that are significantly involved in covalent bonding are known as non-metals.
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PLS HELP
Answer this question and I will mark you the braninliest! <3
Answer:
the left one
Explanation:
heavier means it goes faster
Sulfur reacts with oxygen to form sulfur dioxide (SO2(g), Delta. Hf = â€"296. 8 kJ/mol) according to the equation below. Upper S (s) plus upper O subscript 2 (g) right arrow upper S upper o subscript 2 (g). What is the enthalpy change for the reaction? Use Delta H r x n equals the sum of delta H f of all the products minus the sum of delta H f of all the reactants. â€"593. 6 kJ â€"296. 8 kJ 296. 8 kJ 593. 6 kJ.
The enthalpy of this reaction is -296. 8 kJ/mol.
The equation of the reaction is;
S(s) + O2(g) -----> SO2(g)
Recall that the enthalpy of the reaction can be obtained from the formula;
ΔHrxn = ΔHf(products) - ΔHf(reactants)
We know that;
ΔHf S(s) = 0 KJ/mol
ΔHf O2(g) = 0 KJ/mol
ΔHf SO2(g) = -296. 8 kJ/mol
Hence;
ΔHrxn = -296. 8 kJ/mol - [0 KJ/mol + 0 KJ/mol]
ΔHrxn = -296. 8 kJ/mol
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why is it dangerous to wear contact lenses in the lab
Answer:
It is strongly recommended that students do NOT wear contacts lenses in the laboratory. Chemical vapors may penetrate the contact lens material and cause the lens to adhere to one's eye, which could be detrimental to the eye. Goggles are not vapor tight and do not completely eliminate this absorption.
what is the mechanical hound in the book fahrenheit 451
Explanation:
The Mechanical Hound is a robotic animal that firemen can deploy to hunt and catch fugitives. It can be trained and programmed to hunt its prey very quickly by smell. Once it catches its prey, the Hound injects the person with a sedative; unable to run, the drugged fugitive is easily captured.
what is the empirical formula of cinnamaldehyde?
C9H8O. .....................