Answer:
The "Bohr Model", works only for hydrogen because it considers only the "interactions" between one electron and the nucleus.
Explanation:
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Identify the oxidizing and reducing agent in the following reaction, and determine which element is oxidized and which is reduced. Fe2+(aq) + ClO2(aq) → Fe3+(aq) + ClO2–(aq) ClO2 is the reducing agent and Fe2+ is the oxidizing agent . Fe is oxidized and Cl is reduced. g
Answer:
Explanation:
Fe⁺²(aq) + ClO₂(aq) → Fe⁺³(aq) + ClO₂⁻(aq)
Here oxidation number of Fe is increased from +2 to +3 , so Fe is oxidised .
The oxidation number of Cl is reduced from + 4 to +3 so Cl is reduced .
So ClO₂(aq) is oxidising agent and Fe⁺²(aq) is reducing agent .
All of the following conditions in Earth can cause metamorphic rock to form EXCEPT
O pressure
O heat
the presence of hot, plastic like material
O exposure to air
Explanation:
heat
the presence of hot, plastic like material
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Explanation:
Valves
Blood capillaries
Is lead a representative metal or transitional metal?
Answer:
It's a representative metal
Explanation: Transitional metals are metals of various chemical elements and have valence electrons—i.e., electrons that can participate in the formation of chemical bonds.
Explain how plucking occurs
Answer:
plucking is usually extracting hair
Explanation:
example: pluck the chicken feathers
pluck my brows
For the solution resulting from dissolved 0.32 g of naphthalene (C10H8) in 25 g of benzene (C6H6) at temperature of 26.1°C, calculate the vapor pressure lowering, the boiling point elevation, and the freezing point depression. The vapor pressure of benzene at the temperature of the experiment is 100 torr. (Kf of benzene = 2.67 °C/m, Kb of benzene = 5.12 °C/m)
Answer:
See explanation
Explanation:
Number of moles of naphthalene = 0.32g/128.1705 g/mol = 0.0025 moles
Molality = number of moles/ mass of Solvent in kilograms
Molality = 0.0025/0.025 Kg
Morality = 0.1 m
But
∆T= K × i × m
Where ∆T = boiling point elevation
i= number of particles (this is equal to 1 because naphthalene is molecular and not ionic)
m= molality of naphthalene = 0.1 m
K= boiling point elevation constant = 5.12 °C/m
∆T= 5.12 °C/m ×0.1 = 0.512°C
For freezing point depression
∆T= K× i × m
Where ∆T= freezing point depression
i= number of particles (this is equal to 1 because naphthalene is molecular and not ionic)
m= molality of naphthalene = 0.1 m
K= freezing point depression constant = 2.67 °C/m
∆T= 2.67 °C/m ×0.1 = 0.267°C
From Raoult's law;
∆P = XBPA°
Where;
∆P = vapour pressure lowering
XB = mole fraction of solute
PA° = vapour pressure of pure solvent
Number of moles of solvent = mass/molar mass = 25g/ 78 g/mol= 0.3205 moles
Total number of moles = number of moles of solute + number of moles of solvent = 0.0025 moles + 0.3205 moles = 0.323 moles
Mole fraction of solute = 0.0025 moles/0.323 moles = 0.0077
Vapour pressure of benzene = 100 torr
Therefore;
∆P = 0.0077 × 100torr = 0.77 torr
Hence;
∆P = 0.77 torr
A hydrocarbon molecule contains carbon and hydrogen atoms in equal numbers. Its molar mass is 130.18 g/mol. What is the molecular formula for the hydrocarbon
Answer:
The molecular formula of the hydrocarbon is C10H10
Explanation:
Here, we are interested in finding the molecular formula for the hydrocarbon.
Since there are equal number of moles of carbon and hydrogen, then we have the molecular formula looking like;
CnHn
Kindly recall that the atomic mass of carbon is 12 a.m.u while that of hydrogen is 1 amu
so calculating the atomic mass of the compound, we have;
12(n) + 1(n) = 130.18
13n = 130.18
n = 130.18/13
n = 10.01
So the molecular formula will be C10H10
Answer:
C10H10
Explanation:
A hydrocarbon is a binary compound of carbon and hydrogen. Hence a hydrocarbon is a compound of the general formula (CH)n
Thus;
(12 + 1) n = 130.18
n= 130.18/13
n = 10
Hence the molecular formula of the compound is C10H10
What does this diagram represent?
Answer:
Linear molecule with two domains
Explanation:
For each of the following molecules draw the Lewis structure on a separate sheet of paper. MAKE SURE TO FOLLOW THE RULES FROM CLASS (ie do not break the octet rule unless necessary to connect all the atoms). Then based on your structure indicate:
the total number of valence electrons.
the electronic and molecular shapes (choose from: linear, trigonal planar, bent, tetrahedral, trigonal pyramidal, trigonal bipyramidal, seesaw, T-shaped, octahedral, square pyramidal, or square planar).
whether or not the molecule is polar (Y/N).
Note: The central atom is the first atom listed, except for HCN, H2CO, and OCN-, where carbon is the central atom (underlined).
Formula Valence electrons Electronic Shape Molecular Shape Polar (Y/N)
HCN
PH3
CHCl3
NH4+
H2CO
SO42-
SeF2
CO2
O2
ClO4-
HBr
PF5
BeH2
PO43-
BH3
Br3-
Answer:
Kindly check the explanation section.
Explanation:
Without mincing words let us dive right into the solution to the question above, taking each compound at a time.
NB: Kindly Check attachment for the Lewis Structure of each of the chemical compounds.
Therefore, the number of valence electrons, electronic shape, molecular shape and whether the molecules are polar(Polarity) is given below for each chemical compound.
(1). Compound: HCN
(a). number of valence electrons = 10.
(b). electronic shape =linear.
(c). molecular shape = linear.
(d). Polarity = Y.
(2). Compound: PH3
(a). number of valence electrons = 8.
(b). electronic shape = Tetrahedral.
(c). molecular shape = Trigonal Pyramidal.
(d). Polarity = Y.
(3). Compound: CHCl3.
(a). number of valence electrons = 26.
(b). electronic shape = tetrahedral.
(c). molecular shape = tetrahedral.
(d). Polarity = Y.
(4). Compound: NH4^+
(a). number of valence electrons = 8
(b). electronic shape = tetrahedral
(c). molecular shape = tetrahedral
(d). Polarity = Y.
(5). Compound: H2CO
(a). number of valence electrons = 12.
(b). electronic shape = Trigonal planar.
(c). molecular shape = Trigonal planar
(d). Polarity = Y.
(6). Compound: SO4^2-
(a). number of valence electrons = 32.
(b). electronic shape = Tetrahedral.
(c). molecular shape = Tetrahedral.
(d). Polarity = N.
(7). Compound: SeF2.
(a). number of valence electrons = 20.
(b). electronic shape = Tetrahedral.
(c). molecular shape = bent.
(d). Polarity = Y.
(8). Compound: CO2.
(a). number of valence electrons = 16.
(b). electronic shape = linear.
(c). molecular shape = linear.
(d). Polarity = N.
(9). Compound: O2
(a). number of valence electrons = 32.
(b). electronic shape = Trigonal planar.
(c). molecular shape = Linear.
(d). Polarity = N.
(10). Compound: ClO4-.
(a). number of valence electrons = 32.
(b). electronic shape = Tetrahedral.
(c). molecular shape = Tetrahedral.
(d). Polarity = N.
(11). Compound: HBr.
(a). number of valence electrons = 8.
(b). electronic shape = Linear.
(c). molecular shape = Linear.
(d). Polarity = Y.
(12). Compound: PF5.
(a). number of valence electrons = 40.
(b). electronic shape = Trigonal Bipyramidal.
(c). molecular shape = Trigonal Bipyramidal.
(d). Polarity = N.
(13). Compound: BeH2.
(a). number of valence electrons = 4.
(b). electronic shape = Linear.
(c). molecular shape = Linear.
(d). Polarity = N.
(14). Compound: PO4^3-.
(a). number of valence electrons = 32.
(b). electronic shape = Tetrahedral.
(c). molecular shape = Tetrahedral.
(d). Polarity = N.
(15). Compound: BH3.
(a). number of valence electrons = 6.
(b). electronic shape = Trigonal planar.
(c). molecular shape = Trigonal planar.
(d). Polarity = N
(16). Compound: Br3-.
(a). number of valence electrons = 32.
(b). electronic shape = Trigonal Bipyramidal.
(c). molecular shape = Linear.
(d). Polarity = N.
WHOEVER ANSWERS THIS GETS A SHOUTOUT ON INSTA LIKE I DONT EVEN CARE HELP
The heater used in a 4.33 m x 3.43 m x 3.03 m dorm room uses the combustion of natural gas (primarily methane gas) to produce the heat required to increase the temperature of the air in the dorm room. Assuming that all of the energy produced in the reaction goes towards heating only the air in the dorm room, calculate the mass of methane required to increase the temperature of the air by 7.35 °C. Assume that the specific heat of air is 30.0 J/K-mol and that 1.00 mol of air occupies 22.4 L at all temperatures. Enthalpy of formation values can be found in this table. Assume gaseous water is produced in the combustion of methane.
Answer:
The answer is 7.89
Explanation:
Mass of methane required to increase the temperature of the air in the room by 7.35 °C is 7.95 g
The volume of air in the room is first calculated:
Volume of air in the room = 4.33 m x 3.43 m x 3.03 = 45.00 m³
1 m³ = 1000 L
45.00 m³ = 45.00 m³ * 1000 L/m³
Volume of air in L = 45000 L
Number of moles of air in 45000 L of air is then determined:
1.00 moles of air occupies 22.4 L
number of moles of air in 45000 L = 45000 L * 1 mole / 22.4 L
number of moles of air = 2008.93 moles of air
Energy that is needed to heat the room by 7.35 °C is then calculated:
Quantity of energy needed = Specific heat capacity * number of moles * temperature increase
Specific heat capacity of air = 30.0 J/K/mole
Quantity of energy needed = 30.0 * 2008.93 * 7.35
Quantity of energy needed = 442969.065 J = 443.00 kJ
The amount of methane required to produce that amount of energy is then calculated:
Equation of combustion of methane : CH₄ + 2 O₂ ---> CO₂ + 2 H₂O
Enthalpy of combustion of methane = −890.3 kJ/mole
Number of moles of methane required = 443.00 kJ / 890.8 kJ/mole = 0.497 moles
Mass of 1 mole of methane = 16.0 g
mass of 0.497 moles of methane = 16.0 * 0.497 = 7.95 g
Therefore, mass of methane required to increase the temperature of the air in the room by 7.35 °C is 7.95 g
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What type of energy is defined as the kinetic energy of the atoms of a substance?
Explanation:Thermal energy, or heat, is the energy that comes from the movement of atoms and molecules in a substance. Heat increases when these particles move faster. Geothermal energy is the thermal energy in the earth. Motion energy is energy stored in the movement of objects.
I hope this helped!
What metalloid has commonly been used as an insecticide due
to its effectiveness as a poison.
Answer:
Arsenic.
Explanation:
Hello there!
In this case, since insecticides are substances that act as poisons to get rid of insects in order to prevent their presence and/or reproduction in houses, companies, crops and others, a substance that has been widely used is the metalloid arsenic due to its direct affection of the insect's body (movement, performance, cellular functions).
In addition, high levels of arsenic in food could cause arsenic poisoning in humans as well, that is why such practice must be properly performed and by using the correct security protocol.
Best regards!
Answer:
As
Explanation:
hoffe das hilf jedem in der zukunft
Our universe is made up of at least a
The pH of a solution of 19.5 g of malonic acid in 0.250 L is 1.47.The pH of a 0.300 M Solution of sodium hydrogen malonate is 4.26. What are the values of Ka1and Ka2
Answer:
[tex]Ka_1=1.61x10^{-3}[/tex]
[tex]Ka_2=1.01x10^{-8}[/tex]
Explanation:
Hello.
In this case, since the stepwise dissociation of malonic acid which is a diprotic acid that we are going to symbolize by H₂A, is:
[tex]H_2A\rightleftharpoons H^++HA^-;Ka_1\\\\HA^-\rightleftharpoons H^++A^-;Ka_2[/tex]
The first ionization has the following equilibrium expression:
[tex]Ka_1=\frac{[H^+][HA^-]}{[H_2A]}[/tex]
Whereas the concentration of H⁺ equals the concentration of HA⁻ and is computed via the pH:
[tex][H^+]=[HA^-]=10^{-pH}=10^{-1.47}=0.0339M[/tex]
Next, we compute the molarity of the 19.5 g of malonic acid (molar mass = 104.06 g/mol) as shown below:
[tex][H_2A]=\frac{19.5g/(104.06 g/mol)}{0.250L}=0.750M[/tex]
Thus, Ka1 turns out:
[tex]Ka_1=\frac{(0.0339)(0.0339)}{0.750-0.0339}=1.61x10^{-3}[/tex]
Now, for the second ionization, since the 0.300-M sodium hydrogen malonate is the source of HA⁻, and the pH is 4.26, we can compute the concentration of both H⁺ and A⁻² again by considering the pH:
[tex][H^+]=[A^-^2]=10^{-4.26}=5.50x10^{-5}M[/tex]
Therefore Ka2 turns out:
[tex]Ka_2=\frac{[H^+][A^{-2}]}{[HA^-]}=\frac{(5.50x10^{-5})(5.50x10^{-5})}{0.300-(5.50x10^{-5})}\\ \\Ka_2=1.01x10^{-8}[/tex]
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Why aren’t two hydrogen atoms bonded together considered a compound? Explain.
Answer:
Hydrogen gas (H2) is a molecule, but not a compound because it is made of only one element. Water (H2O) can be called a molecule or a compound because it is made of hydrogen (H) and oxygen (O) atoms. There are two main types of chemical bonds that hold atoms together: covalent and ionic/electrovalent bonds.
atmospheric pressure at elevations of 8000 feet averages about 0.72 atmospheres. Would a cabin pressurized at 500 mm hg meet federal standards
Answer:
Yes, but it must be kept at that value and do not let it to decrease more.
Explanation:
Hello.
In this case, in order to substantiate whether the cabin meet the federal standards, we need to convert the 500 mmHg to atm and compare the result with 0.72 atm by knowing that 1 atm equals 760 mmHg:
[tex]500mmHg*\frac{1atm}{760mmHg} \\\\=0.66atm[/tex]
Thus, since 0.66 atm is 0.06 atm away from the federal standard we can infer that it may meet the federal standard, however, it would not be recommended to let the pressure decrease more than that.
Yes, the cabin pressurized at 500 mm hg meets federal standards.
1 atm is approximately equal to 760 mm Hg. Therefore, the pressure is:
500 mm Hg / 760 mm Hg/atm ≈ 0.65789 atm
So, the cabin pressure of 500 mm Hg is approximately 0.65789 atmospheres. If the atmospheric pressure at an elevation of 8000 feet averages about 0.72 atmospheres, then the cabin pressure of 0.65789 atmospheres would be lower than the ambient atmospheric pressure.
To meet federal standards, cabin pressure should be maintained at an equivalent pressure that allows occupants to breathe comfortably.
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what is functional group of ethers?
Answer:
Explanation:The ether functional group consists of an oxygen atom that forms single bonds with two carbon atoms
Which of these would be classified as a chemical property that could be measured quantitatively?
Volume
Flammability
рн
Solubility
Answer:
рн
Explanation:
From the given choices, pH is the only chemical property that can be measured quantitatively.
A chemical property is one that tells us about what a substance can do as regards to whether or not the substance reacts with other substances.
Examples are flammability, rusting of iron, precipitation, decomposition of water e.t.c
pH is the degree of acidity or alkanility of a solution. It is usually determined quantitatively using a pH scaleThe scale is graduated from 1 to 14 1 to 7 is for acids7 is for neutral compounds7-14 is for alkalines.The smallest unit of an element that can exist either alone or in combination with other such particles of the same or different elements is the
А.
electron
B
proton
neutron
D
atom
Answer:
The answer is D - Atom
The smallest unit of an element that can exist either alone or in combination with other such particles of the same or different elements is the atom.
What is an atom?
An atom is defined as the smallest unit of matter which forms an element. Every form of matter whether solid,liquid , gas consists of atoms . Each atom has a nucleus which is composed of protons and neutrons and shells in which the electrons revolve.
The protons are positively charged and neutrons are neutral and hence the nucleus is positively charged. The electrons which revolve around the nucleus are negatively charged and hence the atom as a whole is neutral and stable due to presence of oppositely charged particles.
Atoms of the same element are similar as they have number of sub- atomic particles which on combination do not alter the chemical properties of the substances.
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Answer:
d
Explanation:
what’s the most abundant isotope of lawrencium
Answer:
266Lr
Thirteen isotopes of lawrencium are currently known; the most stable is 266Lr with a half-life of 11 hours, but the shorter-lived 260Lr (half-life 2.7 minutes) is most commonly used in chemistry because it can be produced on a larger scale.
Explanation:
hopefully that helps you
Which statement describes how this rock was likely formed?
slow cooling of magma beneath the surface of Earth
rapid cooling of magma beneath the surface of Earth
slow cooling of lava on the surface of Earth
rapid cooling of lava on the surface of Earth
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Answer:
A
Explanation:
Slow cooling of magma beneath the surface of earth
To solve this we must be knowing each and every concept related to rock and its formation. Therefore, the correct option is option A among all the given options.
What is rock?Rock is a naturally occurring mineral aggregate that is cohesive and composed of one or even more minerals. These aggregates often take the shape of recognisable and mappable volumes and are the fundamental building block of the solid Earth.
Mineral crystals as well as the sorts of rocks that serve as their hosts cycle through many forms as geologic materials. Temperature, weight, time, and variations in the climate in the Earth's crust and on its surface all play a role in the process. Slow cooling of magma beneath the surface of Earth is the statement that best describes the formation of rock.
Therefore, the correct option is option A.
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where are electrons found in an atom
Answer:
The electrons are found on the outer shell of the atom.
Explanation:
What is the frequency of a wave having 4.90 x 10 -12 J of energy?
Answer:
The answer is
[tex] \huge 7.40 \times {10}^{21} Hz[/tex]
Explanation:
To find the frequency of the wave we use the formula
[tex]f = \frac{E}{h} \\ [/tex]
where
E is the energy
f is the frequency
h is the Planck's constant which is
6.626 × 10-³⁴ Js
From the question
E = 4.90 × 10-¹² J
So we have
[tex]f = \frac{4.90 \times {10}^{ - 12} }{6.626 \times {10}^{ - 34} } \\ [/tex]
We have the final answer as
[tex]7.40 \times {10}^{21} \: \: Hz[/tex]
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HELP ME ASAP!
Under the Law of Multiple Proportions, Carbon Dioxide has a ratio of 2.666 g
Oxygen for every 1 g Carbon. Given this, how much oxygen is present in a sample
of carbon dioxide that has 16 g of carbon?
Answer:
In carbon dioxide, on the right, there is 2.666 g of oxygen for every gram of carbon. So the ratio of oxygen in the two compounds is 1:2, a small whole number ratio
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Why must you avoid touching the gas Spectrum tubes?
Define a function compute_gas_volume that returns the volume of a gas given parameters pressure, temperature, and moles. Use the gas equation PV
Answer:
def compute_volume(pressure,moles,temperature):
volume = (8.314 * moles * temperature)/pressure
print("Volume: "+str(volume))
Explanation:
This line defines the function
def compute_volume(pressure,moles,temperature):
This line calculates the volume
volume = (8.314 * moles * temperature)/pressure
This line prints the calculated volume
print("Volume: "+str(volume))
H3C - CH2 - CEC - CH3
Compound name
Answer:
2-pentene
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Explanation:
If 200.00 mL of a solution of sugar and water contains 0.0025 moles of sugar, what is the concentration of the solution in units of moles per unit volume? Round decimals to the nearest thousandth where applicable. Do not include trailing zeros in decimal answers (e.g., 0.05 instead of 0.050).
Answer:
0.013 mol/L
Explanation:
Molarity, which is molar concentration or moles per unit volume, can be calculated using the formula:
M = n/V
Where; M = Molar concentration of solution
n = number of moles of solute
V = Volume of solvent
n = 0.0025 moles of sugar
V = 200.00mL of solution
Since 0.001L = 1mL
200mL = 0.200L
Therefore, M = n/V
M = 0.0025/0.200
M = 0.0125 mol/L
Round up to the nearest thousandth ~ 0.013mol/L
Given the following balanced equation:
9 Fe2O3 + 2 NH3 → 6 Fe3O4 + N2 + 3 H2O
A) how many grams of NH3 are needed to react with 125 grams of Fe2O3?
B) how many grams of Fe3O4 will be produced?
Answer:
What mass of sodium hydroxide is needed to react completely with 10.0 g of iron( III) chloride? The conversion sequence is: A. B.
Explanation:
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