Answer:
Flammability and oxidation of copper are both chemical properties of a substance.Chemical properties are the properties that tells us how a substance can react with others.Flammability, oxidation of copper, rusting of iron, precipitation e.t.c are chemical properties of a substance.Flammability is one important chemical property of hydrocarbons.Oxidation reaction is peculiar to copper.
Explanation:
what is the applications of electrophilic aromatic substitution reactions
Electrophilic aromatic substitution reactions have various applications in organic chemistry. They are commonly used to introduce functional groups onto aromatic rings, synthesize pharmaceuticals, produce dyes, and create complex organic molecules.
In organic chemistry, electrophilic aromatic substitution reactions are crucial tools for attaching new functional groups to aromatic rings. In these reactions, an electrophile replaces a hydrogen atom on an aromatic molecule. The end output can be used in a variety of different sectors.
Pharmaceutical synthesis is one area in which electrophilic aromatic substitution is used. Chemists can change the solubility, reactivity, and bioavailability of medicinal compounds by selectively adding functional groups to aromatic rings. This enables the creation of fresh medication candidates or the advancement of current ones.
The manufacture of dyes is an additional use. Due to their conjugated systems, aromatic compounds with particular functional groups can display bright hues. Colorful dyes used in textiles, inks, and other industries are produced through the introduction of chromophores onto aromatic rings using electrophilic aromatic substitution processes.
Additionally, it is essential for the synthesis of complex organic compounds to undergo electrophilic aromatic substitution processes. Chemists can create complex chemical structures with particular functions by carefully swapping various locations on an aromatic ring. This makes it possible to synthesize natural substances, sophisticated compounds, and materials with specific qualities.
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what information we get Chemical equation ?
Answer:
We get the following information from a chemical equation :--1. We get the symbol and formulas of the reactants and products.
2. The physical state of the reactants and products.
3. From this reaction, we can know the molecular formula of ammonia, water and nitrogen.
4. Here all the species are in a gaseous state.
5. The reaction takes place at a high temperature and pressure.
6. Zinc metal reacts with dilute sulphuric acid to form zinc sulphate and hydrogen gas. This equation is written as:
Zinc metal reacts with dilute sulphuric acid to form zinc sulphate and hydrogen gas. This equation is written as: Zn+H2SO 4→ZnSO 4 +H2.
a) Water has a molar mass of 18 g/mol and a density of 1000 kg/m3 (or 1 g/cm3). Based on this data, estimate the number of water molecules per unit surface area of water.
b) The coordination number of water (i.e., the average number of "neighbors" each water molecule has) in the liquid state is 4. Neighboring water molecules attract each other via hydrogen bonds, each of which has a binding energy of roughly 10–20 J (although this number depends relatively strongly on temperature). Use this information to estimate the surface tension of water. How does your estimate compare to the observed figure (
γ water = 0.072 N/m ) (hints: Keep in mind that we can think of
surface tension as surface energy per unit area, and consider the energy needed to bring a molecule from the bulk to the surface)?
The estimate is still useful because it provides insight into the behavior of water molecules at the surface of the liquid.
Molar mass of water, M = 18g/molDensity of water, ρ = 1g/cm³ = 1000kg/m³The number of molecules per unit surface area of water can be estimated as follows:Number of water molecules per unit volume of water = Avogadro's number, NA / MNumber of water molecules per unit volume of water = 6.022 × 10²³ / 18 = 3.345 × 10²² / molThe number of molecules per unit surface area of water = the number of molecules per unit volume of water × the thickness of the water layer on the surface= 3.345 × 10²² / m³ × 1 × 10⁻⁸ m= 3.345 × 10¹⁴ / m²b)Given:Coordination number of water, CN = 4Binding energy of hydrogen bond, E = 10⁻²⁰ JThe surface tension of water, γ water = 0.072 N/mEnergy required to bring one molecule from the bulk of the liquid to the surface of the liquid, ΔE= γ water × AThe total binding energy of a water molecule in the liquid state = the binding energy of one hydrogen bond × the coordination number= 10⁻²⁰ J/bond × 4 bonds = 4 × 10⁻²⁰ JThe number of molecules per unit surface area of water = the energy required to bring one molecule from the bulk of the liquid to the surface of the liquid / the total binding energy of a water molecule in the liquid state= ΔE / 4 × 10⁻²⁰= 0.072 / (4 × 10⁻²⁰)= 1.8 × 10²⁰The surface tension of water can also be expressed as follows:γ water = (N / A) × EThe number of hydrogen bonds per unit area, N / A = γ water / E= 0.072 / 10⁻²⁰ = 7.2 × 10¹⁸ / m²The difference between the estimated value and the observed value is relatively large (about a factor of 25). It is because this is just an estimate, and it does not consider all the factors affecting the surface tension of water. However, the estimate is still useful because it provides insight into the behavior of water molecules at the surface of the liquid.
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during dna replication, if one base is substituted for another, __ occurs.
A. antibiotic resistance
B. meiosis
C. mutation
D. protein synthesis
Answer:
mutation
Explanation:
Assume you have 0. 137 mol of dimethylglyoxime (used in the laboratory to test for nickel(ii) ions). What mass of the compound is present?
To determine the mass of dimethylglyoxime present when given 0.137 mol of the compound, we need to use the molar mass of dimethylglyoxime. compound present is 15.91 grams
By multiplying the molar mass by the number of moles, we can calculate the mass of the compound.
Dimethylglyoxime has a molecular formula of C4H8N2O2. To find its molar mass, we add up the atomic masses of carbon (C), hydrogen (H), nitrogen (N), and oxygen (O) in one molecule.
The atomic masses are approximately 12.01 g/mol for carbon, 1.01 g/mol for hydrogen, 14.01 g/mol for nitrogen, and 16.00 g/mol for oxygen.
Molar mass of dimethylglyoxime = (4 × 12.01 g/mol) + (8 × 1.01 g/mol) + (2 × 14.01 g/mol) + (2 × 16.00 g/mol) = 116.12 g/mol
To calculate the mass of 0.137 mol of dimethylglyoxime, we multiply the number of moles by the molar mass:
Mass = 0.137 mol × 116.12 g/mol = 15.91 g
Therefore, when given 0.137 mol of dimethylglyoxime, the mass of the compound present is approximately 15.91 grams.
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what is a Chromosphere
Answer:
The area of a star's atmosphere between its photosphere and corona, such as that of the sun, is referred to as its chromospheric region
the mass number of an element whose atoms contain 18 protons, 22 neutrons and 18 electrons
Answer:
Argon has the chemical formula Ar. Argon has 18 protons and 22 neutrons in its nucleus giving it an Atomic Number of 18 and an atomic mass of 40. Argon is a Noble Gas. Argon is a gas at room temperature.
Explanation:
Find the unit rate. 14 apples for 2 pies
Your answer
Is?
Answer:
7
Explanation:
You have to divide 14 by 2 to find the unit rate/constant of proportionality.
Answer:
7
Explanation:
If a 50kg car is pulling a 30kg car, how much force would be required to accelerate the cars at 2m/s/s?
Answer:
160N
Explanation:
F = m × a
Where;
F = force (Newton)
m = mass (kg)
a = acceleration (m/s²)
According to this question, a 50kg car is pulling a 30kg car. This means that the total mass of the cars is 50kg + 30kg = 80kg
Hence, the force required to accelerate the cars at 2m/s² can be calculated this:
F = 80 × 2
F = 160kgm/s²
F = 160N
Which layer will be the ether layer in a separatory funnel containing diethyl ether and a saturated aqueous solution of nacl?.
The bottom layer will be the ether layer
a mixture in which the solute dissolves until it is no longer able to do so, leaving the undissolved components at the bottom. Solution without saturation. a solution that totally dissolves and leaves nothing behind (but has less solute than the saturated solution) A saturated solution is one that has as much of the solute present as is capable of dissolving. A solution is said to be unsaturated if it doesn't contain all of the solute that can dissolve in it. A saturated solution is one that has as much solute in it as can be dissolved under the circumstances under which it is present.
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How do American cities now protect their water resources
Answer:
They can use man made materials or they can also have designed areas that people can’t go into
Explanation:
When mixed, aqueous solutions of aluminum nitrate, Al(NO3)3, and ammonium carbonate, (NH4)2CO3, will form a precipitate of aluminum carbonate, Al2(CO3)3. The balanced equation is:
2Al(NO3)3(aq) + 3(NH4)2CO3(aq) à Al2(CO3)3(s) + 6NH4NO3(aq)
Which of the following statements regarding this reaction is incorrect?
A)2 moles of Al(NO3)3 will react with 3 moles of (NH4)2CO3.
B)If 6 moles of (NH4)2CO3 react with sufficient Al(NO3)3, 2 moles of Al2(CO3)3 will be formed.
C)If 0.5 mole of (NH4)2CO3 react with sufficient Al(NO3)3, 3 moles of Al2(CO3)3 will be formed.
D)If 1.5 moles of Al2(CO3)3 are formed, given sufficient starting materials, then 9 moles of NH4NO3 will also be formed.
E)4 moles of Al(NO3)3 will react with 6 moles of (NH4)2CO3.
F)If 4 moles of Al(NO3)3 reacts with 9 moles of (NH4)2CO3 there will be left over (NH4)2CO3
The incorrect statement regarding the reaction between aqueous solutions of aluminum nitrate, Al(NO3)3, and ammonium carbonate, (NH4)2CO3, which form a precipitate of aluminum carbonate, Al2(CO3)3 is If 0.5 mole of (NH4)2CO3 react with sufficient Al(NO3)3, 3 moles of Al2(CO3)3 will be formed. Option C.
A chemical equation is a description of the chemical reaction that takes place. It contains the formulae of the reactants and products separated by an arrow. The arrow indicates the direction of the reaction. The stoichiometric coefficients in the equation represent the number of moles of each substance involved in the reaction.
Stoichiometry is a branch of chemistry that deals with the quantitative relationships between reactants and products in a chemical reaction. It's important to keep in mind that the law of conservation of mass applies to chemical reactions. This means that the number of atoms of each element present in the reactants must equal the number of atoms of that element present in the products. Thus, stoichiometry plays a significant role in determining how much product is formed from a given amount of reactant and vice versa. Option C.
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What do the news and science have in common?
What is one of the environmentally damaging effects of "drift-net fishing"?
A) pollution of pristine water sources off the coast line
B) destruction of coral reefs and other valuable ecosystems
C) deepening of ocean channels making it hard for shellfish to survive
D) overharvesting and waste of large populations of non-commercial marine species
Answer: B
Drift-net fishing has many effects, and when the net is put in the water, coral reefs and other oceanic/aquatic plants can be destroyed.
The answer to the question is option B.
what is zn molar mass?
Zn has a molecular mass of 65.3800 g/mol. The mass of one mole of a material, measured in grams per mole (g/mol), is known as molar mass or molar weight.
What is molar mass?
Mass per mole is a definition of molar mass. In other terms, molar mass is the total mass of all the atoms in a substance that makes up a mole. It is measured in gram-per-mole quantities.
For atoms or molecules, molar mass is displayed. The molar mass is simply the element's mass expressed in atomic mass units in the case of solitary elements or individual atoms. To put it another way, an atom's atomic mass and molar mass are precisely equal. Molar mass can be used to determine a particle's identity because it is equivalent to atomic mass for individual atoms. He, for instance, has an atomic mass of 4. There is only one helium molecule in nature, meaning that it has only one atom, so its molar mass is also 4.
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Where are the transition metals found on the periodic table?
The first 5 elements
The bottom two rows
Group 3-11
Groups 3-12
Transition metals are found in groups 3-12 on the periodic table. The correct answer is Groups 3-12.
Transition metals are a group of elements that occupy groups 3-12 on the periodic table. These elements are characterized by having partially filled d orbitals in their electron configurations. The d-block, which consists of the transition metals, is located between the s-block (groups 1 and 2) and the p-block (groups 13-18) on the periodic table.
Transition metals include well-known elements such as iron (Fe), copper (Cu), zinc (Zn), silver (Ag), and gold (Au), among others. They are known for their various physical and chemical properties, such as high melting points, malleability, and ability to form colorful compounds.
By being located in groups 3-12, the transition metals exhibit similar chemical behavior due to the presence of similar electronic configurations in their outermost shells. This allows for the formation of transition metal complexes and their involvement in a wide range of chemical reactions and biological processes.
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how are hydrogen ions essential for the production of atp Hydrogen ion generation is essential for the formation of ATP because a hydrogen ion gradient is used to power ATP synthase during the final stages of cellular respiration, called oxidative phosphorylation. Oxidative phosphorylation occurs in the inner mitochondria membrane.
The production of hydrogen ions is essential for the formation of ATP, as it uses the hydrogen ion gradient to power ATP synthase in the final step of cellular respiration, called oxidative phosphorylation. Oxidative phosphorylation takes place in the inner mitochondrial membrane.
The top of the ATP synthase complex rotates as new hydrogen ions enter. Sufficient energy is present in the ATP synthase complex to synthesize ATP when three protons enter the matrix space. In this way the energy of the hydrogen ion gradient is used to generate ATP. ATP synthase uses a hydrogen ion gradient to help generate ATP, an important energy source for living organisms.
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which example is nonpolar? a. a negative ion b. a neutral ion c. a positive ion d. a molecule with no partial charges
The example that is nonpolar is d. a molecule with no partial charges.
When the charges of the molecule are symmetrical and there are no partial charges, it indicates that the molecule is nonpolar.
Polar molecules have partial positive and negative charges on either end of the molecule.
This occurs as a result of the polarity of the molecule, which is created by the difference in electronegativity between the two atoms forming the bond.
The charge distribution on the molecule is unbalanced due to this polarity, with the electron density more concentrated around the more electronegative atom.
The measurement of the polarity of a molecule is based on the difference in electronegativity between the two atoms forming the bond.
The polarity of a molecule can be determined using various methods, including the dipole moment method, which measures the magnitude of the dipole moment of the molecule.
The dipole moment measures the charge distribution in the molecule and is measured in Debye (D) units, where 1 D = 3.336 × 10-30 Cm.
In conclusion, a molecule with no partial charges is nonpolar.
The other options such as a negative ion, a neutral ion, and a positive ion are polar molecules as they have partial charges on either end of the molecule.
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evaporation is a cooling process and condensation is:
safety: which statement best describes how the system should be heated? do not allow the solvent to boil. heat gently so that the solvent boils and the vapors reach the full height of the condenser. heat gently so that the solvent boils and the vapors extend no more than half way up the condenser. boil as vigorously as possible.
The system should be heated gently so that the solvent boils and the vapors extend no more than halfway up the condenser.
Boiling is the fast vaporization of a fluid, which happens when fluid is warmed to its bubbling point, the temperature at which the vapor weight of the fluid is rise to the weight applied on the fluid by the encompassing air.
There are two fundamental sorts of bubbling: nucleate bubbling where little bubbles of vapor shape at discrete focuses, and basic warm flux bubbling where the bubbling surface is warmed over a certain basic temperature, and a film of vapor shapes on the surface.
In thermodynamics, heating a system, the prerequisite for the bubbling of unadulterated substances to happen is that T divider = T sat. But in genuine tests, bubbling does not happen until the fluid is warmed some degrees over the immersion temperature.
The surface temperature must be to some degree over the immersion temperature in arrange to maintain vapor arrangement.
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in the atom, which particles give the element its identity (atomic number)?
5. suppose you add 2.0 ml of 0.10 m hcl to 100 ml of buffer having 0.10 m ha and 0.20 m naa. the pka of the acid ha is 4.82. a. which species will react strongly with one another? (1 point) b. what will be the ph of the final solution? (2 points)
The species that will react strongly with one another are the acid HA and the base NaA. The pH of the final solution can be calculated by considering the Henderson-Hasselbalch equation.
a) The acid HA and the base NaA will react strongly with one another. HA will donate a proton (H+) to NaA, forming the corresponding conjugate base A- and releasing water. This reaction occurs because HA is a weak acid and NaA is its corresponding conjugate base.
b. To calculate the pH of the final solution, we need to consider the Henderson-Hasselbalch equation, which is pH = pKa + log([A-]/[HA]). Given that the pKa of HA is 4.82 and the initial concentrations of HA and A- are 0.10 M and 0.20 M, respectively, we can plug these values into the equation.
pH = 4.82 + log(0.20/0.10) = 4.82 + log(2) = 4.82 + 0.30 = 5.12
Therefore, the pH of the final solution will be approximately 5.12.
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How many degrees would the temperature of a 45.0 g piece of iron increase if 7,680 J of energy are applied to it? (The specific heat of iron is 0.449 J/g°C)
Question 10 options:
76.6°C
155,000°C
380°C
0.0130°C
Answer:
380
Explanation:
Q=mco
Q is the energy
M is mass
C is specific heat
O is increased in temperature
the following method is used to make crystals of hydrated nickel sulphate.
an excess of nickel carbonate, 12.0g, was added to 40cm^3 of sulphuric acid, 2.0mol/dm^3. the unreacted nickel carbonate was filtered off and the filtrate evaporated to obtain crystals.
A ) number of moles of H2SO4 in 40cm^3 of 2.0mol/dm^3 acid = 0.08
i) number of moles of NiCO3 reacted =
ii) mass of nickel carbonate reacted =
iii) mass of unreacted nickel carbonate =
B ) the experiment produced 10.4g of hydrated nickel sulphate. calculate the percentage yeild.
i) the maximum number of moles of NiSO4.7H2O that could be formed =
ii) the percentage yeild =
(PLS SOLVE WITH STEPS)
Answer:
Explanation:
i) The balanced equation for the reaction between nickel carbonate (NiCO3) and sulfuric acid (H2SO4) is:
NiCO3 + H2SO4 → NiSO4 + CO2 + H2O
From the equation, we can see that one mole of NiCO3 reacts with one mole of H2SO4 to form one mole of NiSO4. Therefore, the number of moles of NiCO3 reacted is equal to the number of moles of H2SO4 in the reaction mixture, which is 0.08 moles.
ii) The molar mass of NiCO3 is 118.7 g/mol, so 0.08 moles of NiCO3 has a mass of:
0.08 moles x 118.7 g/mol = 9.5 g
Therefore, the mass of nickel carbonate reacted is 9.5 g.
iii) The excess of nickel carbonate added to the reaction mixture is:
12.0 g - 9.5 g = 2.5 g
Therefore, the mass of unreacted nickel carbonate is 2.5 g.
B)
i) The molar mass of NiSO4.7H2O is 262.85 g/mol, which includes the mass of seven water molecules. To calculate the maximum number of moles of NiSO4.7H2O that could be formed, we need to use the amount of nickel carbonate reacted (0.08 moles) as the limiting reagent.
From the balanced equation, we know that one mole of NiCO3 reacts to form one mole of NiSO4.7H2O. Therefore, the maximum number of moles of NiSO4.7H2O that could be formed is also 0.08 moles.
The mass of NiSO4.7H2O that could be formed is:
0.08 moles x 262.85 g/mol = 21.028 g
ii) The percentage yield is calculated using the following formula:
percentage yield = (actual yield / theoretical yield) x 100%
The actual yield is given as 10.4 g. The theoretical yield is the mass of NiSO4.7H2O that could be formed, which is 21.028 g.
percentage yield = (10.4 g / 21.028 g) x 100% = 49.4%
Therefore, the percentage yield is 49.4%.
What is the chemical name of the compound K₂SO4?
Answer: Potassium Hydrogen Sulfate
Explanation: The name of the compound K2SO4 is Potassium Hydrogen Sulfate.
Which type of pathway produces carbon dioxide and water?
Cellular respiration can occur either anaerobically (without oxygen) or aerobically. Glucose and oxygen interact during aerobic cell respiration. As byproducts, both water and carbon dioxide are produced.
In glycolysis, are CO2 and water produced?In the majority of cells, glycolysis turns glucose into pyruvate, which mitochondrial enzymes then oxidize to produce carbon dioxide and water. However, due to the absence of mitochondria in some platelets, most notably adult red blood mitochondria, glycolysis serves as the only method of ATP synthesis.
What is the carbon dioxide diffusion pathway?The carbon dioxide moves out of the circulation, via the capillaries, and onto the alveoli where it is ejected, while at the same time oxygen bonds with hemoglobin to be transported back to the tissues once the venous returns to the lungs.
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Cracking of long saturated hydrocarbon chain molecule C40H82 produces 3 octane molecules and the rest as ethane molecules. How many moles of hydrogen are needed to crack one mole of this long hydrocarbon chain? Give your answer in whole numbers.
To determine the number of moles of hydrogen needed to crack one mole of the long saturated hydrocarbon chain (C40H82), we can analyze the reactants and products involved in the cracking reaction.
The cracking reaction is given as: C40H82 -> 3 C8H18 + n C2H6. From the equation, we can see that one mole of the long hydrocarbon chain (C40H82) produces three moles of octane (C8H18) and n moles of ethane (C2H6). Since the cracking process involves breaking the carbon-carbon bonds and forming new carbon-hydrogen bonds, the number of hydrogen atoms in the products should remain the same as in the reactant.
The long hydrocarbon chain (C40H82) contains 82 hydrogen atoms, and the products, 3 moles of octane (C8H18), contain (3 moles) * (18 hydrogen atoms/mole) = 54 hydrogen atoms. Therefore, the number of moles of hydrogen needed for cracking one mole of the long hydrocarbon chain can be calculated as: Number of moles of hydrogen = 82 - 54 = 28 moles. Hence, 28 moles of hydrogen are required to crack one mole of the long saturated hydrocarbon chain (C40H82).
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Had beryllium and calcium already been discovered
Answer:
Yes
Beryllium is a chemical element with the symbol Be and atomic number 4. It is a steel-gray, strong, lightweight and brittle alkaline earth metal. ... Notable gemstones high in beryllium include beryl (aquamarine, emerald) and chrysoberyl.
Calcium is a mineral that is necessary for life. In addition to building bones and keeping them healthy, calcium enables our blood to clot, our muscles to contract, and our heart to beat. About 99% of the calcium in our bodies is in our bones and teeth.
What is the name of the functional group that is attached to this hydrocarbon? The first and last of a chain of three carbons are each single bonded to 3 H; the center carbon is double bonded to O. alkyl halide alcohol carbonyl ketone
Answer:
Ketone
Explanation:
According to the description of the functional group attached to the hydrocarbon - the first and last of a chain of three carbons are each single bonded to 3 hydrogen (H)atoms; the center carbon is double bonded to an oxygen atom, O - it can be deduced that the functional group is a ketone group.
A ketone is a functional group with the structure R₂-C=O, where the two R are alkyl or phenyl groups which may be the same or different. The carbon in a double covalent bond with oxygen is called the carbonyl carbon. The two R groups are bonded to the carbonyl carbon in single covalent bonds.
In the hydrocarbon in this question, the two R groups are methyl groups, CH₃ bonded to the carbonyl carbon. The name of the hydrocarbon is propanone and it is a ketone molecule.
Answer:
Ketone
Explanation:
I’m the _____ state,volume and shape are both definite definite means that those characters and changeable in the _____ common volume and shape or both.
Answer:
I'm the constant, volume and shape are both definite. Constant means that those characters are not changeable in the same common volume and shape or both.
molatilty is measured by using what units? A) g B) L C) Kg D) m
Molality is a measure of concentration and is defined as the number of moles of solute per kilogram of solvent. Molality is typically represented by the symbol "m" and is expressed in the unit of moles per kilogram (mol/kg). Therefore, the correct answer is D) m.
Molality (not molatilty) is indeed a measure of concentration, specifically the amount of solute per kilogram of solvent. It is denoted by the symbol "m" and is expressed in units of moles of solute per kilogram of solvent (mol/kg).
Molality is different from molarity, which is another concentration unit that expresses the amount of solute per liter of solution (mol/L or M).
To clarify, molality is measured in moles of solute (not solvent) per kilogram of solvent (not solute). Therefore, the correct answer is D) m (moles per kilogram).
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