Answer:
To find the density of a box, you will need to divide its mass by its volume. The density of an object is a measure of how much mass is contained in a given volume.
The volume of the box can be calculated by multiplying its length, width, and height:
volume = 2 cm x 4 cm x 10 cm = 80 cm^3
To find the density of the box, you will need to divide its mass by its volume:
density = mass / volume
= 120 g / 80 cm^3
= 1.5 g/cm^3
Therefore, the density of the box is 1.5 g/cm^3.
What is the significance of the half-life of a radioisotope?
A. It tells how long a radioisotope sample is considered dangerous.
B. It tells what kind of radioactivity is released through radioactive
decay.
C. It tells how much energy is released over the lifetime of a
radioactive sample.
D. It tells what fraction of a radioactive sample remains after a
certain length of time.
Answer:
D) It tells what fraction of a radioactive sample remains after acertain length of time.
Explanation:
The molar mass of an insecticide, dibromoethane, is 187.9 g/mol. Its
molecular formula is C2H4Br2. What percent by mass of bromine does
dibromoethane contain?
OA) 42.52%
OB) 2.14%
OC) 85.05%
OD) 12.78%
E) 6.39%
Write a balanced nuclear equation for each of the radioactive decay processes.
Answer: Alpha emission, beta emission, postitron emission,electron capture and gamma emission.
Explanation:
A=- \frac {dN}{dt}Another important atomic clock used for dating purposes is based on the radioactive decay of the isotope carbon-14 As an example, iodine-131 is a radioisotope with a half-life of 8 days. It decays by beta particle emission into xenon-131. After eight days have passed, half of the atoms of any sample of iodine-131 will have decayed, and the sample will now be 50% iodine-131 and 50% xenon-131.
Pancreatic amylase is digestive enzyme found in the small intestine: It helps break down large starch molecules later in the digestive process Pancreatic amylase is unable to break down lipids Which of the following best explains why pancreatic amylase is able to break down starches, but not lipids? enzymes bind only to their specific substrates lipids are too hydrophobic to be broken down by enzymes. enzymes denature in the presence of lipids lipids are too small to bind to enzymes
Pancreatic amylase is able to break down starches, but not lipids because enzymes bind only to their specific substrates.
Pancreatic amylase is the enzyme secreted by pancreas. One of the important features of all the types of enzymes is the substrate specificity. It ensures that enzyme perform the chemical reaction they are specifically intended to do.
We also see salivary amylase secretion in the mouth which begins the breakdown process of our food. It is again directed towards carbohydrates for instance starch. Lipids are digested by emulsification and proteins are digested by breakdown through peptidases.
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predict which aqueous solution will have the lowest freezing point
A. 0.25MOL/LITER SUCROSE
B. 0.15 MOL/LCaCl2
C. 0.15MOL/LNaCl
D. 0.2MOL/LNaNO3
CaCl₂ has lowest freezing point as it has higher "im" value.
What is freezing point?A solution's freezing point is lower than that of the pure solvent's. It follows that freezing cannot happen until a solution is lowered to a temperature lower than the pure solvent.
As we know more "im" value lowest is the freezing point.
Here,
m = molarity
i = van't Hoff factor = 1 + (n-1) α
α = degree of ionization
n = number of ions.
A. 0.25 MOL /LITER SUCROSE = 0.25 M SUCROSE
m = 0.25 M
Sucrose is non-electrolyte, so α = 0
or, i = 1 + (n-1) × 0
or, i = 1
So, im = 1 × 0.25 M
im = 0.25 M
B. 0.15 MOL/L CaCl₂ = 0.15 M CaCl₂
m = 0.15 M
CaCl₂ → Ca⁺² + 2Cl⁻
no. of ions (n) = 3
CaCl₂ is electrolyte, so α = 1
Thus, i = 1 + (3-1) × 1
or, i = 3
So, im = 3 × 0.15 M
or, im = 0.45 M
C. 0.15 MOL/L NaCl = 0.15 M NaCl
m = 0.15 M
NaCl → Na⁺ + Cl⁻
no. of ions = 2
NaCl is electrolyte, so α = 1
Thus, i = 1 + (2-1) × 1
or, i = 2
So, im = 2 × 0.15 M
or, im = 0.30 M
D. 0.2 MOL/L NaNO₃ = 0.2 M NaNO₃
m = 0.2 M
NaNO₃ → Na⁺ + NO₃⁻
no. of ions = 2
NaNO₃ is electrolyte, so α = 1
Thus, i = 1 + (2-1) × 1
or, i = 2
So, im = 2 × 0.2 M
or, im = 0.40 M
Among these four aqueous solution, CaCl₂ has higher "im" value thus it has lowest freezing point.
Correct option: B
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what is the rate constant of a reaction if rate = .2 (mol/L)s, [A] and [B] are each 3M, m=1 and n=2
Answer: [tex]7.407 \times 10^{-3} \text{ M}^{-2} \text{ s}^{-1}[/tex]
Explanation:
Note that rate is equal to [tex]k[A]^m [B]^n[/tex], where [tex]k[/tex] is the rate constant, [tex][A][/tex] and [tex][B][/tex] are the concentrations, [tex]m[/tex] is the order of reactant A, and [tex]n[/tex] is the order of reactant B.
Substituting the given values,
[tex]0.2=k(3^1)(3^2) \implies k=7.407 \times 10^{-3} \text{ M}^{-2} \text{ s}^{-1}[/tex]
chromium has 24 electrons. write out the entire electron configuration for chromium using spdf notation
Using spdf notation, the electron configuration for chromium is [Ar] 3d5 4s1 whose atomic number is 24.
In the sixth column of the periodic table chromium is the first element. It is under the transition metal category. Along with its 24 protons and 24 electrons, the most common form of chromium also has 28 neutrons. The placement of electrons in various atomic orbitals is known as the electronic configuration. The various appropriate orbitals will be filled with electrons.
The s orbitals can accommodate two electrons, while the p orbitals can accommodate six, the d orbitals can accommodate ten, and the f orbitals can accommodate fourteen electrons. Chromium has an atomic number of 24. Chromium has the electrical configuration 1s22s22p63s23p64s13d5.
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The enthalpy change for the following reaction is -318 kJ. Using bond energies, estimate the O-F bond energy in OF2(g). OF2(g) + H2O(g) -> O2(g) + 2HF(g)
The enthalpy change for the following reaction is -318 kJ. Using bond energies, estimate the O-F bond energy in OF₂(g).
OF₂(g) + H₂O(g) -> O₂(g) + 2HF(g) is 190 kJ /mol.
The reaction is given as :
F - O - F + H - O - H -----> O = O + 2H - F
moles bond energy
bond broken H - O 2 463 kJ/mol
bond broken O - F 2 ?
bond form O = O 1 498 kJ/mol
broken form H - F 2 565 kJ/mol
enthalpy change = BE ( bond broken ) - BE (bond form )
- 318 = (2 (O - F) + 2(463) - (( 498 ) + 2( 565))
- 318 = 2 (O - F) - 698
2 (O - F) = 380
(O - F) = 190 kJ /mol
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Determine the mass in grams of 7.68 x 10^21 atoms of carbon. (The
mass of one mole of carbon is 12.01 g.)
Mole measure the number of elementary entities of a given substance that are present in a given sample. Therefore, the mass in gram of 7.68 x 10²¹atoms of carbon is 0.152g.
What is mole?The SI unit of amount of substance in chemistry is mole. The mole is used to measure the quantity of amount of substance. It measure the number of elementary entities of a given substance that are present in a given sample. There are so many formula for calculating mole.
we know one mole of any element contains 6.022×10²³ atoms which is also called Avogadro number
mole =given number of atoms ÷ 6.022×10²³(Avogadro number)
given number of atoms of carbon=7.68 x 10²¹atoms
Substituting the values
mole= =7.68 x 10²¹÷ 6.022×10²³
mole = 0.0127moles of carbon
number of moles of carbon=given mass of carbon÷ molar mass of carbon
Substituting the values
0.0127= mass of carbon÷12.01g
mass of carbon= 0.152g
Therefore, the mass in gram of 7.68 x 10²¹atoms of carbon is 0.152g.
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Which of the following statements concerning a face- centered cubic unit cell and the corresponding lattice, made up of identical atoms, is incorrect? A. If the atoms have radius r, then the length of the cube edge is √8 times f. B. The close-packed direction lies along the face diagonal of the unit cell. C. The coordination number of the atoms in the lattice is V8. D. There are four atoms per unit cell in this type of packing. E. All statements are correct.
A. If the atoms have radius r, then the length of the cube edge is √8 times f statements concerning a face- centered cubic unit cell and the corresponding lattice, made up of identical atoms, is incorrect.
How effectively does the FCC crystal structure pack?74% of the FCC lattice's space is used for packing. Let n be the number of atoms or spheres, where n is equal to 4, and let r be the radius of the sphere and a be the length of the cube's edges.
A face-centered cubic unit cell structure is made up of atoms organized in a cube with a fraction of an atom at each corner and six extra whole atoms at the center of each cube face.
In this unit cell, there are 14 lattice points, eight of which are corner atoms while the remaining six are located in the middle of each face.
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If an ideal gas has a pressure of 1.11atm, a temperature of 40.04°C, and a volume of 76.87L, how many moles of gas are in the sample?
n=? mol
The numbers is moles in the gas sample is 0.032
Since we know that the I deal gas equation is
PV=nRT
where ,
P is pressure
V is volume
n is no. of moles
R is gas constant (8.3145 J⋅mol^−1⋅K^−1)
T is temperature ( in Kelvin)
P =1.11 atm
T = 40.04 + 273
= 313.04 K
V= 76.87L
substituting the given values in the ideal gas equation we get,
1.11x76.87=n x 8.3145 x 313.04
n=(1.11x76.87)/(8.3145x313.04)
n=0.032
Hence the moles in the sample are 0.032 .
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Suppose the material used to create this graph was being cooled (reading the graph going right to left ← ). What change of state is represented by line segment B?
The point at which a liquid turns into a solid is referred to as its freezing point. In principle, a solid's melting point and liquid's freezing point should coincide. Small variations between these numbers can be seen in real-world situations.
The melting point and freezing point of a substance are the same temperature because freezing happens at the same temperature as melting. The temperature at which a substance becomes liquid or solid is known as the melting or freezing point of that substance.
Liquid water freezes at temperatures below 32°F (0°C); this temperature is known as the freezing point of water. Pure water ice melts and turns into liquid water at temperatures higher than 32°F (0°C);
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to determine the unknown concentration of copper ions in solution, you will first prepare a calibration curve. the calibration curve plots
Use equation: (C=m/V). Now, the known concentration of copper(ll) ion solution and a colorimeter to produce a cu(ll) ion conc./absorbance calibration curve. you will be able to read its conc. from the curve.
How is titration used to determine an unknown concentration?A titration is a technique in which a solution of known concentration is used to determine the concentration of an unknown solution. The titrant (the known solution) is added from a buret to a known quantity of the analyte (the unknown solution) until the reaction is complete.
What is the use of calibration curve?A calibration curve is a way to identify the concentration of an unknown compound. These curves use data points of known compounds at varying concentrations, and researchers or developers can use these curves to find where an unknown substance plots.
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A piece of wood from an ancient Egyptian tomb is tested for its carbon-14 activity. It is found to have an activity per gram of carbon of A=10decay/min⋅gA=10decay/min⋅g. Carbon-14 has an initial activity of 15decay/min⋅g15decay/min⋅g and a half-life of 5730 years. In years, what is the age of wood?
The age of wood 2880 years.
What are tombs from ancient Egypt?People who passed away would be interred in the tombs of the Ancient Egyptians.This was significant to the Egyptians because they held the view that as long as a person was properly buried in their tomb, life remained even after death.
What other name would you give an Egyptian tomb?The sarcophagus was intended to serve as the occupants' eternal home in the afterlife, according to ancient Egyptian belief.Pharaohs and rich citizens' sarcophagi were ornately decorated with carvings and painting.
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calculate the amount of heat needed to boil of hexane (), beginning from a temperature of . be sure your answer has a unit symbol and the correct number of significant digits.
The formatted answer to the question is below.Energy required to boil hexane is 80kj
From the question, the parameters given are 64.7g of hexane,C6H14; a starting temperature of 41.9°C and bringing it to 33.2°C.
Molar mass of hexane,C6H14=86.18g/mol.
Things to know: heat capacity of hexane, C6H14= 142.6J/molK, the heat of fusion = 9.87 kj/mol.
STEP ONE(1): ENERGY USED IN MELTING HEXANE SOLID.
Using the formula below;
Energy used in melting the solid(in JOULES) = (mass of hexane/molar mass of hexane) × heat of Fusion.
=(64.7g of C6H14/86.18(g per mol) of C6H6) × 9.87 kJ per mol.
= 7.40J.
= 0.0074 kJ.
STEP TWO (2): ENERGY OF HEATING THE LIQUID.
It can be calculated from the formula below;
Energy= heat capacity (J/g.K) × mass of hexane× (∆T).
= 142.6J/molK × 64.7× (41.9-33.2).
= 80268.114
= 80.268 kJ.
Energy required to boil hexane= Energy required to melt the hexane + energy required for boiling.
= 0.0074 kJ.+80.268 kJ.
= 80.27kJ
Approximately, 80kJ
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What volume in milliliters of CO gas would be produced by the complete reaction of 2.40 g of C solid at STP according to the following reaction? Remember 1 mol of an ideal gas has a volume of 22.4 L at STP.
C(s) + H₂O(g) → CO(g) + H₂(g)
How do i start the equation we need the stoichometry to do this
Answer: 4480 mL
Explanation:
2.40 grams of C is equal to [tex]2.40/12.011=0.19981683456831[/tex] moles of C.
From the reaction equation, for every mole of C consumed, one mole of CO is produced.
This means that 0.19981683456831 moles of CO are produced.
Therefore, the volume in milliliters is [tex](0.19981683456831)(22.4)(1000)=4480[/tex] mL.
The volume of CO gas produced by the complete reaction of 2.40 g of C solid at STP is approximately 4.47 L (or 4470 milliliters).
To calculate the volume of CO gas produced, we first need to determine the number of moles of C reacting. Given that 2.40 g of C is provided, we can convert this mass to moles using the molar mass of carbon (12.01 g/mol).
Moles of C = Mass of C / Molar mass of C
Moles of C = 2.40 g / 12.01 g/mol
Moles of C ≈ 0.1998 mol
Now, we use stoichiometry from the balanced chemical equation to find the number of moles of CO produced. From the equation, the molar ratio between C and CO is 1:1.
Moles of CO = Moles of C
Moles of CO ≈ 0.1998 mol
Finally, we use the ideal gas law at STP (22.4 L/mol) to calculate the volume of CO gas:
Volume of CO gas = Moles of CO * 22.4 L/mol
Volume of CO gas ≈ 0.1998 mol * 22.4 L/mol
Volume of CO gas ≈ 4.47 L
So, the volume of CO gas produced by the complete reaction of 2.40 g of C solid at STP is approximately 4.47 L (or 4470 milliliters).
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write the formula for compounds formed from these pairs of ions. a) nh4 , so32- b) calcium ion, phosphate ion
The compound that is formed from the combination of NH₄⁺ and SO₃²⁻ is (NH₄)₂SO₃ and the compound that is formed from the combination calcium ion and phosphate ion is Ca₃(PO₄)₂.
Definition of Ionic bond
A bond that is formed by the complete transfer of some electrons from one atom to another is known as an ionic bond. The atom which loses one or more electrons becomes a cation—a positively charged ion. The atom which gains one or more electron becomes an anion—a negatively charged ion.
The term "ionic bonding" is given "when the ionic character is greater than the covalent character".
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URGENT/
Drag the tiles to the correct locations. Each tile can be used more than once, but not all tiles will be used. Some locations will remain empty.
Chloramine has the chemical formula NH2Cl. Nitrogen has five valence electrons, each hydrogen has one valence electron, and chlorine has seven valence electrons. Complete the Lewis structure for this covalent compound.
The lewis structure of Chloamine can be given as above.
What is Covalent Compound?If one element shares electron with another elements to form bond. This is called as covalent bond. The compound which contain Covalent bond called Covalent compound.
What is Nitrogen atom?Nitrogen is one of the elements of periodic table. It has 7 as atomic number and 14 as mass number. Its electronic configuration is 1s2 2s2 2p3. It belongs to 15th group and 2nd period of the periodic table. It accept three electron to get stable electronic configuration.
As we know that, chloramine has the chemical formula NH2Cl. Nitrogen has five valence electrons, each hydrogen has one valence electron, and chlorine has seven valence electrons.
Thus, we concluded that Nitrogen form three single bond two with hydrogen and one with chlorine atom.
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How does the balanced equation relate to the law of conservation of matter?
Answer:
The law of conservation of mass states that matter cannot be created or destroyed. If we have an unbalanced equation, atoms are either destroyed or created, which totally violates this law
Alex pipettes out 10 mL of 1.5 M AgNO3 solution and dilutes it to make the total volume of 30 mL. What is the concentration of the new solution?
PLEASE HELP
Which of the following coenzymes participate in the reactions of the pyruvate dehydrogenase complex? 1. thiamine pyrophosphate (TPP) 2. lipoic acid (lipoamide) 3. Flavin adenine dinucleotide (FAD) 4. Nicotinamide adenine dinucleotide (NAD) 5. Coenzyme A (CoA) View Available Hint(s)All of the listed coenzymes participate. O Only 1,2, and 4 participate. O Only 1,2, and 3 participate. O Only 1, 3, and 5 participate. Submit
The right answer is E.
The decarboxylation of pyruvate to acetyl-CoA and the production of NADH and CO2 are irreversible reactions that are catalyzed by the multi-enzyme complex known as pyruvate dehydrogenase. Pyruvate is introduced into the TCA cycle through the complex.
Two regulatory enzymes, three catalytic enzymes, and a binding protein make up the enzyme complex. There are three enzymes:
1. Thiamine pyrophosphate (TPP) is used as the prosthetic group by pyruvate dehydrogenase (E1).
2. Dihydrolipoyl transacetylase (E2), which has as its prosthetic groups coenzyme A and lipoamide.
3. Nicotinamide adenine dinucleotide (NAD+) and flavin adenine dinucleotide (FAD) serve as cofactors for dihydrolipoyl dehydrogenase (E3).
Hence, The correct response is option E since E2 needs coenzyme A as one of its co-factors.
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A gas is transported in a horizontal pipeline at a flow of 10.000 lb.„/min. If it is moving at 10 ft.'s, what rate of work (in horsepower) must be performed on the gas to increase its velocity to 200 ft/s at the same temperature and pressure (I hp 550
A gas is transported in a horizontal pipeline at a flow of 10.000 lb.„/min. If it is moving at 10 ft.'s, -6045 HP rate of work (in horsepower) must be performed on the gas to increase its velocity to 200 ft/s at the same temperature and pressure
What is rate of work?This equation may be used to compute work: Work equals Force x Distance. The Newton metre is the SI unit for work (N.m). One joule is the amount of work done when one Newton of force pushes an item one metre.
Because the force transmits one unit of energy when it does one unit of work, the rate of accomplishing work equals the rate of utilising energy. A horsepower is equivalent to 550 foot pounds per second, while a kilowatt is equal to 1000 watts.
Given that,
A gas is transported in a horizontal pipeline at a flow of 10.000 lb/min
m = (10000÷60) lb/sec
m = 166.67 lb/sec
and, v₁ = 10 ft/sec
v₂ = 200 ft/sec
Now,
or, m [(v₂² - v₁²)/2] = - w
or, w = m/2 × [(v₁² - v₂²)]
or, w = 166.67/2 × [(10)² - (200)²]
or, w = -3325000 lb. ft².s⁻¹
or, w = -3325000 / 550 HP
or, w = -6045 HP
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which of the following are considered biofuels? select all that apply. check all that apply cellulosic ethanolcellulosic ethanol grain ethanolgrain ethanol methane from sewage and manuremethane from sewage and manure natural gas from shalenatural gas from shale biodiesel from soybean oilbiodiesel from soybean oil wind energy wind energy coal
The cellulosic ethanol cellulosic ethanol grain ethanol grain ethanol methane are considered biofuels. The two most common biofuels used today are ethanol and biodiesel.
Both of which are the first generation biofuel technologies. The BETO is working with industry to develop next-generation biofuels from waste, the cellulosic biomass, and algae-based resources. Ethanol (often derived from corn in the United States and sugarcane in Brazil), biodiesel (derived from vegetable oils and liquid animal fats), green diesel (derived from algae and other plant sources), and the biogas are examples of the biofuels (methane derived from animal manure and other digested organic material).
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lans.
2. A sample containing 1.80 mol of argon gas has a volume of 10.00 L. What is
the new volume of the gas, in litres, when each of the following changes occurs in
the quantity of the gas? Assume that pressure and temperature remain constant.
The changes are not cumulative. T
(a) An additional 1.80 mol of argon gas is added to the container. [ans: 20.0 L]
(b) A sample of 25.0 g of argon gas is added to the container. [ans: 13.5 L]
(c) A hole in the container allows half of the gas to escape. [ans: 5.00 L]
(a) An additional 1.80 mol of ar gas is added to the container.[ans:20.0L]
(b) A sample of 25.0 g of ar gas is added to the container.[ans:13.5 L]
(c) A hole in the container allows half of the Ar gas to escape.[ans:5.00 L]
How do I compute?(a) The container is filled with 1.80 mol more argon gas.
The gas would now have a new volume of 20.0 L.
(a) To the container is inserted a sample of 25.0 g argon gas.
We must first establish how many moles of argon gas are included in the 25.0 g sample in order to calculate the new volume of the gas. The molar mass of argon, which is 39.948 g/mol, can be used to accomplish this. Thus, the 25.0 g sample has a total of 0.625 moles of argon. The volume of the gas will grow in proportion to the amount of gas present because the pressure and temperature are both constant. The total amount of gas will be 2.425 moles since 1.80 moles of gas and 0.625 moles of gas are being combined. The gas will now have a new volume of 13.5 L (10.00 L * (2.425 moles / 1.80 moles)).
(c) A hole in the container allows half of the argon gas to escape.
The new volume of the gas would be 10.00 L / 2 = 5.00 L.
How can the new volume of a gas be determined?Calculate the change in volume using the Ideal Gas Law, PV=nRT P V = n R T.
What is the gas's volume?The area occupied by gaseous particles under normal temperature and pressure circumstances is referred to as the volume of gas. It is identified as a "V." The letter "L" stands for "liters," the SI unit of volume. At normal temperature, a mole of gas has a volume of 24 m3, or 24 000 cm3.
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throughout the extraction steps of this week's oxidation reaction procedure, which of the following compound(s) is/are present in the bottom layers? group of answer choices sodium acetate sodium chloride and sodium acetate 9-fluorenone sodium chloride
The organic phase is a solvent, usually dichloromethane or diethyl ether, that disperses very little in water. The 9-fluorenone was dried, isolated, and saltified with sodium sulfate.
What are the three primary types of extraction techniques?There are a number of extraction processes, including solvent extraction, distillation, pressing, and sublimation, that can be used. Solvent extraction is the method that is most frequently used.
What kind of extraction is most typical?extracting liquid from liquid When a substance is "extracted," it is moved from a solid or liquid into a separate solvent or phase. The method most frequently used in chemical labs is liquid-liquid extraction, which takes place in a separatory funnel.
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A certain liquid X has a normal boiling point of 126.00 °C and a boiling point elevation constant K(b) = 1.63 °C kg*mol^-1. A solution is prepared by dissolving 1 some iron(III) chloride (FeCl3) in 600. g of X. This solution boils at 127.3 °C. Calculate the mass of FeCl3, that was dissolved. Round your answer to 2 significant digits.
The molality of the solution from the elevation of boiling point and elevation constant is obtained as 0.79 molal. From this, the weight of iron chloride is added is 77.6 g.
What is molality?Molality of a solution is the ratio of the number of moles of solute to the mass of solvent in kg. The elevation in boiling point of a solution by the addition of a solute is proportional to the molality by the equation:
ΔT = Kb m.
Given ΔT = 127.3 - 126 = 1.3 °C.
Kb = 1.63 °C Kg /mol.
mass of solvent = 600 g = 0.6 Kg
molality = ΔT / Kb
= 1.3 °C / 1.63 °C Kg /mol
= 0.79 mol/kg.
Molality = 0.79 Kg/mol = number of moles of FeCl₃ / 0.6 Kg
no.of moles of FeCl₃ = 0.79 Kg /mol × 0.6 Kg = 0.47 moles
Therefore, the mass of FeCl₃ added is:
= no.of moles × molar mass
= 0.47 × 162.3 g/mol = 77.61 g.
Therefore, the mass of FeCl₃ added is 77.61 g.
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consider the following electron configurations to answer the questions that follow: (i) 1s2 2s2 2p6 3s1 (ii) 1s2 2s2 2p6 352 (iii) 1s2 2s2 2p6 3s2 3p1 (iv) 1s2 2s2 2p6 3s2 3p4 (v) 1s2 2s2 2p6 3s2 3p5 the electron configuration of the atom with the most negative electron affinity is
The electron configuration of the atom with the most negative electron affinity is 1s² 2s² 2p⁶ 3s¹ sodium (Na)
When an atom gains an electron, there is an energy change called electron affinity.
Eea = X(g) + e⁻ ⇒ XE
E stand for change in energy (E)
Eea stands for electron affinity.
Affinity for electrons frequently has negative energy levels. An electron can be added to an atom more readily the more negative the electron affinity. The periodic table shows that electron affinities increase with period.
Because electrons are added to energy levels, which brings them closer to the nucleus, there is a stronger attraction between the nucleus and its electrons, increasing electron affinity higher for the groups and from left to right across periods of a periodic table.
However, a few exceptions:
1. Elements in group 18 (8A) have electron affinities that are larger than zero. This is due to the atom's filled valence shell, which prevents an electron from being added without it moving to a lower energy shell.
2. Because adding an electron necessitates that it stay in the previously vacant p sub-shell, group 2 (2A) elements have higher electron affinities.
3. Due to the necessity of adding an electron to an orbital that is already occupied, group 15 (5A) elements have higher electron affinities.
Putting these things into practice with the components listed in the question
(i) 1s² 2s² 2p⁶ 3s¹ = 11 Sodium (Na)
(ii) 1s² 2s²2p⁶ 35² = 15 Phosphor (P)
(iii) 1s² 2s² 2p⁶ 3s² 3p¹ = 13 Aluminum (Al)
(iv) 1s² 2s² 2p⁶ 3s² 3p⁴ = 16 Sulfur( S)
(v) 1s² 2s² 2p⁶ 3s²= 12 Magnesium (Mg)
We knew that, electron affinity increases upward for the groups and from left to right across periods so, the electron congifuration that have the most negative electron affinity is sodium (Na) 1s² 2s² 2p⁶ 3s¹ .
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Density is a common physical property of substances that can give insight into the structure of the substance on the atom or molecular level. You are attempting to measure the thickness of a rectangular piece of aluminum found at a crime scene, but it is too thin for your ruler. You know density has units of g/mL, and you recall mL is the same as cm?. Sooo...why not use the volume of the metal, the length and height? to find the volume by water displacement, you lower the sample into a graduated cylinder with an initial volume of water of 32.9 ml. the volume of water rises to 48.1 ml. you also mass the sample and determine it to be 20.28 g. finally, you measure the length of the solid to be 6.5 cm and the height to be 5.1 cm. from this information determine the thickness of the metal rectangular solid(mm).
The length of the solid to be 6.5 cm and the height to be 5.1 cm. the thickness of the metal rectangular solid(mm) is 4.58 mm.
given that :
height of solid = 5.1 cm
length of solid = 6.5 cm
the initial volume of graduated cylinder = 32.9 mL
the final volume of graduated cylinder = 48.1 mL
the volume of the solid = 48.1 - 32.9
= 15.2 mL = 15.2 cm³
the volume expression for the solid is given as :
volume = length × width × height
15.2 cm³ = 6.5 cm × width × 5.1
width = 15.2 / 33.15
Width = 0.458 cm = 4.58 mm
Thus, the thickness of metal = 4.58 mm
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A pregnant client experienced preterm labor at 30 weeks gestation. Upon assessing the client the nurse finds that the newborn is at risk of having cerebral palsy. Which medication administration should the nurse perform to prevent cerebral palsy in the newborn?
A. Calcium gluconate.
B. Magnesium sulfate.
C. Glucocorticoid drugs.
D. Antibiotic medications
The medicine that has to be given by the nurse to prevent cerebral palsy in the new-born is magnesium sulphate.
The term "cerebral palsy" refers to a collection of conditions that impair mobility and posture development and are thought to be caused by non-progressive abnormalities. Insults that caused cerebral palsy are thought to have happened during foetal development or early childhood. A significant risk factor for cerebral palsy is preterm delivery, and that risk rises sharply as gestational age decreases. Right now, 25% of all new occurrences of cerebral palsy are caused by babies delivered before 34 weeks of pregnancy. Cerebral palsy risk is higher when there are several pregnancies. MgSO4 was infused continuously at a rate of 2 g/h for up to 12 hours after a 6 g loading dose. Given before delivery, magnesium sulphate is known to regulate the vasculature and minimize hypoxia effects by neutralising cytokine or excitatory amino acid damage, which may lower the risk.
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1000 mg vanco in 250ml of d5w over 2 hrs. what is the drip rate ?
There is 1000 mg Vanco in 250 ml of 5w over 2 hrs. The drip rate of Vanco is 125 ml/hr.
What is the drip rate?Drip rate is a term used to describe the rate of an intravenous infusion depending on the number of drops (gtt) given to the patient each minute.
To conduct this calculation, you must know the total volume to be infused in milliliters, as well as the infusion time. Use the following formula.
To calculate the drip rate. The volume of the medicine is divided by the number of hours.
Given, the number of hours = 2 hrs
The volume of the Vanco is = 250ml
250 / 2 = 125 ml/hr
Therefore, the drip rate is 125 ml/hr.
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