Atomic mass of bromine is 80 g. The mass of four moles of molecular bromine (Br₂) is 640 g. The correct alternative is not given.
To find the mass of four moles of molecular bromine (Br₂), you can use the formula:
mass = moles × molar mass
The molar mass of Br₂ is the atomic mass of bromine multiplied by two, since there are two atoms of bromine in each molecule of Br₂. So the molar mass of Br₂ is:
molar mass of Br2 = 80 g × 2 = 160 g
Now you can plug in the values for moles and molar mass into the formula:
mass = 4 moles × 160 g = 640 g
So the mass of four moles of molecular bromine (Br₂) is 640 g.
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which element has the lowest 1st ionization energy? A. As B.P C. N. D.Bi E.Sb
The element has the lowest 1st ionization energy is N ( nitrogen). Th correct answer is C.
First, the energy needed to remove one electron from a neutral atom in order to create a positive ion is referred to as the ionization energy or ionization potential. It is described as the energy difference between a neutral atom's and a positive ion's ground states.
The ease with which an atom can lose electrons and produce positive ions makes the initial ionization energy a crucial chemical feature of an element.
Higher first ionization energy suggest that removing an electron from an atom is more challenging, whereas lower first ionization energies suggest that removing an electron from an atom is simpler.
For each element, the first ionization energy varies, and it can be used to determine an element's electron configuration, electron affinity, reactivity, and chemical behavior.
Since nitrogen is a nonmetal, it has a lower initial ionization energy than metal elements like bismuth (Bi) or antimony (Sb).
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Mica has two metal blocks made from the same substance. She heats both blocks on the same stove for the same amount of time. She then measures the temperature. Metal Block A has a higher temperature than Metal Block B.
This situation is possible if Metal Block A has a lower specific heat capacity than Metal Block B. Specific heat capacity is the amount of heat energy required to raise the temperature of a substance by one degree Celsius per unit of mass.
What is specific heat?Specific heat is the amount of heat energy required to raise the temperature of one unit of mass of a substance by one degree Celsius or Kelvin. It is a characteristic property of a substance and is expressed in units of J/(g·°C) or J/(g·K). Substances with a higher specific heat require more energy to raise their temperature compared to substances with a lower specific heat.
Here,
If a substance has a lower specific heat capacity, it means that it requires less heat energy to raise its temperature. So, if both blocks are made from the same substance but have different specific heat capacities, heating them for the same amount of time on the same stove would result in Metal Block A having a higher temperature than Metal Block B.
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according to the information in the graphs and the table how was species diversity in the aquatic ecosystems affected by the increased water temperature
Species diversity in aquatic ecosystems is significantly affected by the increased water temperature. This is because warm water holds less dissolved oxygen than cool water, and may not contain enough dissolved oxygen for the survival of different species of aquatic life.
What is an ecosystem?An ecosystem may be defined as a type of place or an area where members of different species live together and interact with one another for the purpose of food, shelter, space, mating partner, and other resources.
The solubility of oxygen and other gases will decrease as temperature increases. This means that colder lakes and streams can hold more dissolved oxygen than warmer waters. If water is too warm, it will not hold enough oxygen for aquatic organisms to survive.
Some compounds are also more toxic to aquatic life at higher temperatures. So, warm stream water is can affect the aquatic life in the stream.
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Classify each solid as a covalent, ionic, metallic, or molecularsolid.sodium sulfide, pure sodium, frozen carbon dioxide, diamond.
The classification of solid are :
Sodium sulfide - ionic solid
Pure sodium - metallic solid
Frozen carbon dioxide - molecular solid
Diamond - covalent solid
The sodium sulfide that is Na₂S is the compound formed by the ionic bonding. The sodium sulfide is classified as the ionic solid. The pure sodium exhibits the metallic bonding and comes under the metallic solid. The frozen carbon dioxide also called as the dry ice is the molecular solid.
The diamond is the network of the covalent bonding. Therefore the diamonds comes under the category of the covalent solid. The covalent bonds are formed between the atoms by the sharing of the electrons.
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The volume of oxygen at STP given by IL of 10 volume solution of H2O2 is
a) IL
b) 10L
c) 0.1 L
d) 100 L
What is the name for N2F4?
The chemical name for N2F4 is Dinitrogen tetrafluoride. It is also known as Tetrafluoro hydrazine.
Tetrafluoro hydrazine have the chemical formula N2F4. It is a colorless, reactive inorganic gas. It is also called as perfluoro hydrazine and is a fluorinated analog of hydrazine. This is a highly hazardous chemical that explodes in the presence of organic materials. Tetrafluoro hydrazine is manufactured from nitrogen trifluoride. It is manufactured by using an iron catalyst or iron(II) fluoride. It is used in chemical syntheses as a precursor or a catalyst. At room temperature, N2F4 is mostly associated with only 0.7% in the form of NF2. It was considered for use as a high energy liquid oxidizer. This is also called as Dinitro tetrafluoride.
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what is the average distance between oxygen molecules at stp?
The average distance between oxygen molecules at STP is approximately 1.9 × 10^-8 cm.
What is Atomic Radius ?
Atomic radius is the distance between the nucleus of an atom and its valence electrons. It is typically measured in picometers (pm) or angstroms (Å) and is used to describe the size of an atom. The atomic radius can vary depending on the element and its electronic configuration, and can also vary in different states (ionization states, for example). The trend for atomic radius generally increases down a group on the periodic table and decreases across a period from left to right.
where P is the pressure, V is the volume, n is the number of moles of gas, R is the gas constant, and T is the temperature.
The volume of one mole of gas at STP is 22.4 L according to the molar volume of a gas.
For oxygen gas (O2), the molar mass is approximately 32 g/mol. Therefore, one mole of oxygen gas contains 6.02 × 10^23 oxygen molecules.
Using the ideal gas law, we can solve for the volume of one oxygen molecule:
V = (RT/P) * (1/n)
V = (0.0821 L atm/mol K * 273 K / 1 atm) * (1 / 6.02 × 10^23 molecules)
V ≈ 4.0 × 10^-23 L
The volume of one oxygen molecule is incredibly small, so the average distance between oxygen molecules at STP is very close to zero. However, we can estimate the average distance by assuming that the molecules are arranged in a regular pattern, such as a simple cubic lattice.
In a simple cubic lattice, each oxygen molecule is surrounded by six nearest neighbors. The distance between adjacent molecules is equal to the cube root of the volume of one molecule and its six neighbors:
d = (V_molecules/6)^(1/3)
d = (4.0 × 10^-23 L / 6)^(1/3)
d ≈ 1.9 × 10^-8 cm
Therefore, the average distance between oxygen molecules at STP is approximately 1.9 × 10^-8 cm.
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Calculate the molar mass of NaBr?
The molar mass of NaBr will be 102.89 g/mol.
Sodium bromide (NaBr) is a white crystalline ionic compound that is made up of sodium cations (Na⁺) and bromide anions (Br⁻). It is used in various applications, including as a sedative, in the oil industry, and in the manufacture of photographic chemicals.
The molar mass of NaBr can be calculated by adding the atomic masses of sodium (Na) and bromine (Br) in one mole of NaBr. The atomic mass of sodium is 22.99 g/mol and the atomic mass of bromine is 79.90 g/mol, as found in the periodic table.
Therefore, the molar mass of NaBr is:
Molar mass of NaBr = atomic mass of Na + atomic mass of Br
Molar mass of NaBr = 22.99 g/mol + 79.90 g/mol
Molar mass of NaBr = 102.89 g/mol
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Do You Know If Milk Is an Acid or a Base?
Milk is considered to be slightly acidic.
This is because it contains lactic acid, which gives it a slightly sour taste. However, it is not as acidic as substances like vinegar or lemon juice. The pH of milk is typically around 6.5-6.7, which is just below neutral on the pH scale (neutral is 7.0).
Mammary glands in mammals generate milk, a clear liquid meal. Before they can digest solid food, it serves as a young mammal's main source of nutrition. Milk immunity is a result of immune-related and immune-modulating elements.
It is important to note that the pH of milk can vary depending on factors such as the type of cow, the cow's diet, and the processing of the milk. However, in general, milk is considered to be an acid rather than a base.
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what distinguishes the atoms of one element from another?
The atoms of one element are distinguished from another based on their atomic number, Each element has a unique number of protons in its nucleus, which gives it a unique atomic number.
For example, all carbon atoms have 6 protons in their nucleus, which gives carbon its unique atomic number of 6. All oxygen atoms have 8 protons in their nucleus, which gives oxygen its unique atomic number of 8. This means that the atomic number of an element determines its chemical properties and its position in the periodic table.
In addition to the number of protons, atoms of the same element can have different numbers of neutrons in their nucleus, which gives rise to different isotopes of the element.
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The noble gas shorthand configuration for ruthenium would have which noble gas as its core?
(a) He
(b) Ne
(c) Ar
(d) Kr.
The noble gas shorthand configuration for ruthenium would have Kr noble gas as its core.
Generally, the electron configuration of an element describes how electrons are distributed among its atomic orbitals. Basically, electron configurations of atoms follow a standard notation in which all electron-containing atomic subshells along with the number of electrons they hold written in superscript and are placed in a sequence.
The electronic configuration of Kr is given as,
Kr = [Ar] 3d¹⁰ 4s² 4p⁶
Hence, the atomic number of ruthenium is 44. So, the noble gas used for shorthand configuration for ruthenium is Krypton (Kr).
Therefore, the correct option is D.
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what is the type of polyester that gets formed in the reaction between ethylene glycol and phthalic anhydride?
The polyester that is formed in the reaction between ethylene glycol and phthalic anhydride is called polyethylene terephthalate (PET).
PET is a thermoplastic polymer that is used in a wide range of applications, including textile fibers, packaging films, and engineering plastics. It is formed by the condensation polymerization of ethylene glycol and terephthalic acid (or its dimethyl ester), but phthalic anhydride can also be used in place of terephthalic acid.
In the reaction between ethylene glycol and phthalic anhydride, the two monomers undergo a condensation reaction to form a linear polyester chain with ester linkages between the monomer units. This polyester chain can then undergo further reactions to form a variety of different structures and materials.
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Function c is defined by the equation c(n)=50+4n. It gives the monthly cost, in dollars, of visiting a gym as a function of the number of visits, n. In this situation, what information would the inverse function give us? find the inverse function. Find the value of c(7). Show your reasoning and explain what the value means in this situation.
The inverse function of c(n) would give us the number of visits n as a function of the monthly cost c.
To find the inverse function, you will have to write n in terms of c (which means number of visits as function of monthly cost). To do this, you can rearrange the equation c(n) = 50 + 4n to obtain n = (c - 50) / 4.
The value of c(7) is c = 50 + 4n = 50 + 4(7) = 78 . This means that if you spend 78 dollars on a gym every month, you will have made 7 visits in total.
Additionally, it can also be useful to find the inverse function of c(n) if you have a budget in mind but don't know how many visits you can make within that budget. In this case, you can plug your budget into the inverse function to figure out how many visits you can make with the given amount of money.
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What is the ideal molecular geometry for SF6?
The Sulfur hexafluoride molecule, SF₆ consists six fluorine atoms with sulfur as central atom. Thus the ideal molecular geometry for SF₆ is octahedral.
Sulfur hexafluoride, or SF₆, is an inorganic greenhouse gas. It is non-flammable, odorless and colorless. In order to determine the Lewis structure of any molecule, we must first know the total number of valence electrons. Here we find the total number of valence electrons for SF₆, by adding the valence electrons for the sulfur and fluorine atoms. Total valence electrons in SF₆
= Sulfur valence electrons + Fluorine valence electrons. Total number of valence electrons in SF₆= 6 + 7×6 = 6 + 42
= 48 valence electrons
SF₆ therefore has 48 valence electrons.
Now look at the sulfur hexafluoride molecule, the sulfur is in the central position with the fluorine atoms arranged symmetrically around it. The atoms are arranged in an octahedral pattern, making the molecular geometry of SF₆ octahedral.
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What is CS2 called in chemistry?
The compound CS₂ is called carbon disulfide in chemistry.
With the chemical formula CS₂ and the structural formula S=C=S, carbon disulfide (commonly known as carbon disulfide) is a significant inorganic molecule in chemistry. It is a white liquid that serves as a component in the synthesis of organic compounds.
Several industries utilise carbon disulfide. Many compound like Rubber, viscose rayon, cellophane are made up of it.
The group of inorganic substances known as other non-metal sulfides includes CS₂. These are inorganic compounds with a sulfur atom in an oxidation state of 2, where the most massive atom linked to the oxygen is a member of the other non-metals group.
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A rigid container holds 22. 4 l of an ideal gas at stp. How many moles of gas need to be added to the container to make the pressure equal to 325 kpa?.
Avogadro's law states that 2.2075 moles must be added to the container in order to raise the pressure to 325 kPa.
What is meant by Avogadro's law?The general number of atoms or molecules has a direct relationship to the volume occupied by a gas under constant temperature and pressure, according to Avogadro's law, a gas law.
Given that it links temperature, pressure, volume, and substance amount, it is closely related to the ideal gas equation.
V ∝ n,
The straight line graph of volume versus moles is a straight line passing through the origin which implies that zero moles of gas occupy zero volume.
As 1 atm = 101.325 kPa
325 kPa = 325/101.325 = 3.2075 atm, as at STP 1 atm =22.4 liter.
Applying Avogadro's law,
n₂ = 71.848 × 1/22.4 = 3.2075 moles .
To estimate moles to be added, we get
3.2075 - 1 = 2.2075 moles.
Therefore, to increase the pressure in the container to 325 kPa, 2.2075 moles of gas must be supplied.
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What is the general name for H2SO4?
The general name for H₂SO₄ is sulfuric acid.
Sulfuric acid is a strong acid that is commonly used in a wide range of industrial and laboratory applications, such as in the production of fertilizers, dyes, detergents, and explosives, among others. It is a dense, oily, and colorless liquid that is soluble in water and has a very high boiling point of 337 °C (639 °F).
It is also used as a laboratory reagent for various chemical reactions, and as an electrolyte in lead-acid batteries. It is a very strong acid that is capable of reacting with most metals, and it can cause severe burns and eye damage upon contact with the skin or eyes. Therefore, it should be handled with extreme caution and protective equipment should always be used when working with it.
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Nuclear power plants produce no _________________________________________ but they do generate ____________________________________________________.
Answer:
Green house gas emissions but do generate heat to produce steamsince power plans don't burn fuel, they don't produce greenhouse
Explanation:
Nuclear power plants produce no greenhouse gas emissions but they do generate electricity.
What are Nuclear power plants ?Nuclear power plants are a type of power generation facility that harnesses the energy from nuclear reactions to produce electricity.
Unlike fossil fuel power plants, which burn coal, oil, or natural gas and release greenhouse gases into the atmosphere, nuclear power plants do not emit any greenhouse gases during their operation.
This is because nuclear power plants rely on nuclear fission, a process where the nucleus of an atom is split, to generate heat.
The heat is then used to produce steam, which drives turbines connected to generators, ultimately generating electricity.
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What is a skeleton equation give example?
Which type of isomer differs in the covalent arrangement of atoms?
Types of isomers that differ in the arrangement of covalent atoms are structural isomers.
Definition of IsomersIsomers are compounds with the same molecular formula but different structural formulas and do not necessarily share the same properties. Generally, isomers have similar chemical properties to each other. In general, isomers are divided into two, namely structural isomers and geometric isomers.
Structural isomers occur due to differences in the arrangement of structural bonds between atoms and functional groups in a molecule. There are three types of structural isomers namely skeletal isomers, positional isomers and functional group isomers.
Geometric isomers are isomers that are caused by a limitation of free rotation of a bond in a molecule. In contrast to structural isomers, these isomers occur only in compounds that have a rigid bond with two dissimilar sides and, usually, occur in alkenes.
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a polar covalent bond between two atoms results from
Two atoms with various electronegativity levels. The electrons in a bond are not distributed equally when one atom is bound to a more electronegative atom. Polar covalent bonds are this kind of bond.
What is a covalent bond?A chemical link known as a covalent bond includes the sharing of electrons to create electron pairs between atoms. These electron pairs are referred to as shared pairs or bonding pairs. When atoms share electrons, a constant balance between the forces that pull them in opposite directions results in covalent bonding. Atoms share electron pairs through covalent connections. H-H or C-H are examples of nonpolar covalent bonds involving atoms with similar or identical electronegativity, while polar covalent bonds are formed when unequal electronegativity is shared across atoms (e.g., H–O). A shared electron pair is the Lewis definition of a covalent bond. In hydrogen chloride, a hydrogen atom and a chlorine atom form the following chemical connection.To learn more about covalent bond refer to:
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What is the generic name for Pepcid used to treat GERD?
Famotidine is the name of the generic version of Pepcid, a drug used to treat gastroesophageal reflux disease (GERD).
Famotidine is a member of a group of drugs known as histamine-2 (H2) blockers, which lessen the formation of stomach acid. Famotidine can aid in the relief of GERD symptoms such heartburn, regurgitation, and difficulty swallowing by lowering the quantity of acid in the stomach. There are several different formulations of famotidine, including tablets, capsules, and oral suspension.
Famotidine is a medication that belongs to a class of drugs known as histamine-2 (H2) blockers. It is used to decrease the production of stomach acid and is commonly used to treat conditions such as gastroesophageal reflux disease (GERD), peptic ulcer disease, and Zollinger-Ellison syndrome.
It works by blocking the action of histamine, a chemical in the body that stimulates the stomach to produce acid. By reducing the amount of acid in the stomach, famotidine can help relieve the symptoms of acid reflux and ulcers, such as heartburn, indigestion, and stomach pain.
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Calculate bond order of N2?
Bond order of N2 is 3. It is a naturally occurring as a diatomic gas. N2 has a triple covalent bond between the nitrogen atoms.
The bond order is defined as a formal measure of the multiplicity of a covalent bond between two atoms. Bond order is the difference between the numbers of electron pairs in bonding and antibonding molecular orbitals. It is the number of bonding pairs of electrons between the two atoms. A single bond has a bond order of one and a double bond has a bond order of two and a triple bond has a bond order of three in a covalent bond. A high bond order indicates that there is more attraction between the electrons. A higher bond order means that the atoms are held more tightly together. It indicates the stability of the bond. There is the greater the stability with higher bond order.
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Select all the characteristics that apply to an atomic orbital. Defined by the wave function (Psi). A region around the nucleus of an atom where the probability of finding an electron is high A shell in an atom containing the valance electrons Identified by a unique combination of four quantum numbers; identified by a unique combination of three quantum numbers Defined by the square o' the wave function
The correct option is (a), an area where there is a high chance of finding an electron is the nucleus of an atom.
Identified by a unique combination of four quantum numbers; identified by a unique combination of three quantum numbers. Defined by the wave function (Psi) or the square of the wave function (|Psi|²). An atomic orbital is a mathematical function that describes the probability of finding an electron at a particular location in an atom. The wave function (Psi) defines the shape of the orbital, and the square of the wave function (|Psi|²) gives the probability density of finding an electron at a particular location. The quantum numbers that identify an atomic orbital include the principal quantum number (n), the angular momentum quantum number (l), the magnetic quantum number (m), and the spin quantum number (s). The values of these quantum numbers determine the energy, shape, and orientation of the orbital. An atomic orbital does not refer to a shell in an atom containing the valence electrons, as a shell is a collection of orbitals with the same principal quantum number (n). Valence electrons are the outermost electrons in an atom and are located in the highest energy level, which may consist of one or more shells.
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The boiling point of methane is__
The boiling point or temperature at which methane molecule, CH₄, in its liquid state starts to form vapours is equals to the -258.9°F.
Methane: The molecular formula of methane is CH₄. Like other chemical compounds, methane also has physical properties, including boiling point, melting point, freezing point, etc. The boiling point is the temperature at which methane becomes a gas. The boiling point is the temperature at which the pressure exerted by the surroundings on the liquid equals the pressure exerted by the vapor of the liquid. It is a molecule with no hydrogen bonding (visible only between N/O/F and H), and since hydrogen bonding is by far the strongest intermolecular force, methane boils the coldest. It also has no permanent dipole permanent dipole forces due to it being tetrahedral so all the dipoles cancel and thus boils at a very low -162 °C. Therefore, the boiling point of methane is -258.9°F.
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Select all of the reasons why water is essential to life.
- It dissolves a wide variety of substances.
- It plays a role in many chemical reactions.
- It regulates temperature.
Water is essential to life for multiple reasons, including its ability to dissolve a wide variety of substances, play a role in chemical reactions, and regulate temperature. (All Options)
Water is a unique and versatile substance that plays a crucial role in supporting life on Earth. One of its most important properties is its ability to dissolve a wide variety of substances, which makes it a vital component of many biological processes. For example, water helps to transport essential nutrients, minerals, and waste products throughout the body. Additionally, water plays a central role in many chemical reactions, such as those that occur in metabolic processes and energy production.
Finally, water is a good conductor of heat and helps to regulate temperature, which is essential for maintaining the stability of biological systems. Overall, water is an essential component of life and its properties play a critical role in supporting the diverse range of living organisms found on Earth.
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When water freezes, it freezes the salt with it.
True
False
Answer: False
When salt water or any other liquid that has some type of particle in it, freezes the salt or particles sink to the top or bottom, depending on weather it is more dense than the liquid it is meaning B. False is our correct answer.
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The volume of a balloon was 4.21 L when the temperature was 25.0 °C, what will the volume of the balloon be when the temperature is
50.0°C?
is agno3 soluble in water
AgNO₃ is soluble in water .
Strong ionic bonds combine to generate a silver nitrate molecule. It indicates that the compound's two constituents, silver and nitrate, retain opposing charges and are drawn to one another.
Thus, nitrate is negatively charged whereas silver is positively charged. Because it possesses an additional ion, silver acquires a positive charge during the production of silver nitrate. In contrast, nitrate loses an ion.
Consequently, their charges are combined and balanced. Yet, the silver and nitrate separate when submerged in water. This explains why silver nitrate dissolves in water.
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Which is the strongest interparticle force present in a sample of H3PO4? a. dipole―dipole forces b. ionic bonding forces c. ion―induced dipole forces
d. dispersion forces e. ion―dipole forces f. hydrogen bonding forces g. dipole―induced dipole forces
The strongest interparticle force present in the sample of H₃PO₄ is the correct is e. ion―dipole forces.
The intermolecular force of the attraction is the molecule H₃PO₄ that is phosphoric acid is the ion - dipole forces. The ion - dipole force is the attractive force that will results from the electrostatic attraction in between the ion and the neutral molecule that will have the dipole. The intermolecular force of attraction is the attractive and the repulsive forces that will arise in between the molecules of the substance.
Thus, the H₃PO₄ that is phosphoric acid sample has the strongest ion - dipole forces of intermolecular attraction.
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