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If the vapor pressure of water at 25°C is 23.56 torr, then the vapor pressure of the solution is 21.77 torr.

According to thye question,

Mass of NaCl = 20.0 g

Molar mass of NaCl = 58.5 g/mol

Moles of NaCl = Given mass/ Molar mass [tex]=\frac{20}{58.5} =0.34188[/tex]

NaCl in aqueous solution completely dissociates as:

Moles of Na+ = 0.34188

Moles of Cl- =  0.34188

Given, mass of water = 150.0 g

Water has a molar mass of 18 g per mol.

Moles of water [tex]=\frac{150}{18}=8.33333[/tex]

Therefore, total moles in solution

=  Moles of water +  Moles of Na+ + Moles of Cl-

=  8.33333 +  0.34188  +   0.34188

= 9.017

Mole fraction of water in solution

= Moles of water/ Total moles

[tex]\frac{8.33333}{9.017} =0.9242[/tex]

Again, From Raoult's law,

We know,

Water's solution's vapor pressure as a volatile component

=  (Mole fraction of water) x (Vapor pressure of pure water)

= 0.9242 x 23.56  torr

= 21.77 torr

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To determine if a gamma ray of a given wavelength has enough energy to remove an electron from a hydrogen atom, we need to calculate the energy of the gamma ray and compare it to the ionization energy of a hydrogen atom.

First, let's calculate the energy of the gamma ray. The energy of a photon can be calculated using the equation:

E = hc/λ

where:

h = Planck's constant (6.626 x 10^-34 J s)

c = speed of light (2.998 x 10^8 m/s)

λ = wavelength of the gamma ray (1.00 x 10^-8 cm)

Now we can plug in the values:

E = (6.626 x 10^-34 J s) * (2.998 x 10^8 m/s) / (1.00 x 10^-8 m)

E = 1.98 x 10^-18 J

Next, let's calculate the ionization energy of a hydrogen atom. The ionization energy of hydrogen is the minimum amount of energy required to remove an electron from the hydrogen atom. It is given as 13.6 eV, which can be converted to joules:

13.6 eV * 1.60 x 10^-19 J/eV = 2.18 x 10^-18 J

Finally, we compare the energy of the gamma ray (1.98 x 10^-18 J) to the ionization energy of hydrogen (2.18 x 10^-18 J). Since the energy of the gamma ray is less than the ionization energy of hydrogen, we can conclude that it does not have enough energy to remove an electron from a hydrogen atom.

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The correct option is C. the compound with the greatest surface tension in the liquid phase: NCl3.

The four nitrogen compounds gave comprise of a nitrogen iota reinforced with three molecules of a halogen. That means every one of the four compounds have similar number of iotas and a similar focal molecule yet with an alternate halogen in each compound. The data got some information about are bond length and extremity, which rely upon atomic size and electronegativity. Since the focal molecule is something similar and the wide range of various iotas have a place with a similar gathering then the pattern for atomic size and electronegativity is utilized to decide the overall bond length and extremity.

Going down the gathering of halogens, the atomic size increments and electronegativity diminishes. The compound with the longest bond is the compound with the biggest, and least electronegative, halogen, which is iodine. In this way, nitrogen triiodide has the longest bonds. Concerning extremity, fluorine is the most electronegative and iodine is the most un-electronegative with chlorine being equivalent to nitrogen in electronegativity. Subsequently, nitrogen trifluoride has the most polar bonds and nitrogen triiodide has the most un-polar bonds.

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The formula for lithium sulfide is Li2S, indicating two lithium atoms and one sulfur atom in each molecule.

Lithium sulfide is a binary ionic compound made out of lithium and sulfur. Its synthetic equation is Li2S. This equation shows that every particle of lithium sulfide contains two lithium molecules and one sulfur iota. Lithium sulfide is an unscented, white or light dim strong that is solvent in water and delivers a soluble arrangement. It is areas of strength for a specialist and responds overwhelmingly with water to create lithium hydroxide and hydrogen sulfide gas. Lithium sulfide is in many cases utilized as a beginning material for the union of other lithium compounds and as a part in lithium-particle batteries, which are broadly utilized in compact electronic gadgets.

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The molar mass of acetone is approximately 58.08 g/mol.

The chemical formula of acetone is C₃H₆O. To calculate its molar mass, we need to find the atomic masses of each element in the compound and then add them up based on the molecular formula.

The atomic masses of carbon (C), hydrogen (H), and oxygen (O) are 12.01 g/mol, 1.01 g/mol, and 16.00 g/mol, respectively.

The molar mass of acetone can be calculated as follows:

Molar mass of acetone = (3 x atomic mass of C) + (6 x atomic mass of H) + (1 x atomic mass of O)

Molar mass of acetone = (3 x 12.01 g/mol) + (6 x 1.01 g/mol) + (1 x 16.00 g/mol)

Molar mass of acetone = 58.08 g/mol

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Measuring absorbance at two wavelengths is necessary to differentiate between compounds with similar absorption spectra, and determine their concentrations in a solution. This is important in analytical chemistry, particularly spectrophotometry and colorimetry.

What is absorbance?

Absorbance is a measure of how much light is absorbed by a substance as it passes through a solution. It is calculated as the logarithm of the ratio of the intensity of incident light to the intensity of transmitted light, according to the Beer-Lambert law. The more a substance absorbs light, the higher its absorbance will be. Absorbance is commonly used in analytical chemistry to determine the concentration of a particular analyte within a solution, based on its absorbance characteristics at specific wavelengths.

Hence, the answer is, measuring absorbance at two wavelengths is necessary to differentiate between compounds with similar absorption spectra, and determine their concentrations in a solution.

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To compare the emissions of a propane-burning car to that of a gasoline-burning car, we need to calculate the amount of CO2 produced from a single tank of gas for each fuel. Here's how it can be done:

Propane:

A single tank of propane contains 40.0 kg of fuel. From the balanced equation for propane combustion, we know that for every 1 mole of propane burned, 3 moles of CO2 are produced.

We can use the molar mass of propane (44.1 g/mol) to convert the amount of fuel to moles:

40.0 kg × 1000 g/kg ÷ 44.1 g/mol = 909.1 moles

So, 909.1 moles of propane would be burned, producing:

909.1 moles × 3 moles CO2/1 mole propane = 2727.3 moles CO2

Finally, we can use the molar mass of CO2 (44.0 g/mol) to convert the amount of CO2 to grams:

2727.3 moles × 44.0 g/mol = 120167.2 g

And then, to convert the amount of CO2 to kilograms:

120167.2 g ÷ 1000 g/kg = 120.2 kg CO2

So, from a single tank of propane, 120.2 kg of CO2 would be produced.

Gasoline (2,2,4-trimethylpentane):

A single tank of gasoline contains 40.0 kg of fuel. From the balanced equation for gasoline combustion, we know that for every 1 mole of gasoline burned, 8 moles of CO2 are produced.

We can use the molar mass of gasoline (114.2 g/mol) to convert the amount of fuel to moles:

40.0 kg × 1000 g/kg ÷ 114.2 g/mol = 349.6 moles

So, 349.6 moles of gasoline would be burned, producing:

349.6 moles × 8 moles CO2/1 mole gasoline = 2796.8 moles CO2

Finally, we can use the molar mass of CO2 (44.0 g/mol) to convert the amount of CO2 to grams:

2796.8 moles × 44.0 g/mol = 122957.1 g

And then, to convert the amount of CO2 to kilograms:

122957.1 g ÷ 1000 g/kg = 122.9 kg CO2

So, from a single tank of gasoline, 122.9 kg of CO2 would be produced.

From the calculations above, we can see that a car burning gasoline produces slightly more CO2 than a car burning propane from a single tank of fuel.

The process of transformation of any liquid substance into a solid is comprehended as freezing. The temperature below which any material advents transforming its phase to solid from the liquid is understood as that material's freezing point.

Freezing is that process that begins taking place when the temperature is lowered down enough. Due to the decreased temperature, the transition occurs at the molecular level as the molecule's rate turns on decreasing. Due to the substantial slow down the molecules become incapable to confound the attractive forces among them. As an effect, the configuration of molecules along the specified positions takes place and directs to the phenomenon of freezing.

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Pressure can be defined as the force applied per unit area on a surface.

It is a measure of how much force is exerted on an area of a surface. The SI unit for pressure is the Pascal (Pa), which is equivalent to one Newton (N) of force per square meter (m²) of area.

In simpler terms, pressure is the amount of force applied to a surface divided by the area of that surface. The greater the force applied to a surface, the greater the pressure; and the larger the surface area, the lower the pressure.

Pressure is an important concept in science and engineering, and is used in a variety of applications, such as measuring atmospheric pressure, hydraulic pressure, and blood pressure.

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The correct combination holding the potential to indicate spontaneous reactions is +ΔS, -ΔH.

As the naming of both ∆H and ∆S is given, so let us understand their definition. Enthalpy is representative of total energy of the system along with product of pressure and volume. It refers to energy content.

Entropy, on the other hand, is randomness or unavailable energy of a system. Now spontaneity of the reaction refers ability to carry out a reaction without requiring external energy. As obvious, the system with excess energy or releasing the energy and less unusable energy can carry out spontaneous reaction.

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The mass of the compound that would be expected to form if 85.2 g of iodine were used in the experiment is 56.0 g. This can be calculated using the mass ratio of iodine to fluorine and the original data.

To find the expected mass of the compound, we first need to calculate the mass of fluorine that was used in the original experiment:

From this, we can find the mass of fluorine by dividing the mass of the compound by the mass ratio of iodine to fluorine:

We can then use this data to find the expected mass of the compound that would form if 85.2 g of iodine were used instead:

This is the expected mass of the compound that would be produced in the experiment if 85.2 g of iodine were used.

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The average mass of element X is 51.2 amu, which is closer to 54 amu than to 50 amu.

Isotopes are variants of an element that have the same number of protons in their atomic nuclei but different numbers of neutrons.

To determine whether the average mass of the element X is going to be closer to 50 amu or 54 amu, we can calculate the weighted average of the masses of the two isotopes, taking into account their natural abundances.

The formula for calculating weighted average is:

avg mass = (abundance of isotope 1 * mass of isotope 1) + (abundance of isotope 2 * mass of isotope 2)

In this case, we have:

abundance of isotope 1 = 70%

mass of isotope 1 = 50 amu

abundance of isotope 2 = 30%

mass of isotope 2 = 54 amu

Upon substituting the values into the formula, we get:

average mass = (0.7 * 50 amu) + (0.3 * 54 amu)

average mass = 35 amu + 16.2 amu

average mass = 51.2 amu

So the average mass of element X is 51.2 amu, which is closer to 54 amu than to 50 amu. This is because the second isotope has a higher mass and a higher natural abundance than the first isotope, so it contributes more to the overall mass of the element X.

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A shielded nucleus will absorb uplift from a deshielded nucleus and will have a lower chemical shift.

Generally, in nuclear magnetic resonance (NMR) spectroscopy, the chemical shift is defined as a measure of the resonance frequency of a nucleus relative to a reference compound. The chemical shift usually depends upon the electronic environment of the nucleus, which is affected by nearby atoms or groups of atoms.

Basically, when a nucleus is shielded, it means that there are electrons or electron-donating groups nearby which reduces the external magnetic field experienced by the nucleus. And this results in a lower resonance frequency or higher chemical shift due to the reason that nucleus requires less energy to achieve resonance.

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Hexane is a type of structural isomer.

Structural isomers are molecules that have the same molecular formula but different arrangements of atoms. In the case of hexane, it is an organic compound with the molecular formula [tex]C_6H_{14}[/tex], and it has five different isomers due to the different arrangements of its carbon atoms.

The simplest form of hexane is n-hexane, which has a straight chain of carbon atoms. The other four isomers, 2-methylpentane, 3-methylpentane, 2,3-dimethylbutane, and 2,2,3-trimethylbutane, all have branching in their carbon chains.

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The atoms that comprise a molecule are held together by chemical bonds. Chemical bonds can also hold molecules to one another. Water molecules are joined to one another by hydrogen bonds.

What exactly is a chemical bond?

The atoms or ions that come together to create a molecule or the molecules that combine to make a substance are held together by a force of attraction. It is in charge of keeping the individual atoms or molecules together. The energy is released when chemical bonds are formed. Chemical bonds bind substances together. Chemical bonds that hold molecules together also form temporary connections vital for life.

Ionic, covalent, hydrogen, and London dispersion forces are examples of chemical bonding.

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Might cause the mass of a product to be more than the theoretical mass are impurities, incomplete reactions, and measurement errors.

There are several factors that could cause the mass of a product to be more than the theoretical mass:
1. Impurities: If there are impurities present in the reactants or the product, this could cause the mass of the product to be more than the theoretical mass.
2. Incomplete reactions: If the reaction is not allowed to go to completion, there may be unreacted reactants left in the product, which could increase the mass of the product.
3. Measurement errors: If there are errors in the measurement of the reactants or the product, this could cause the mass of the product to be more than the theoretical mass.

In conclusion, impurities, incomplete reactions, and measurement errors are all factors that could cause the mass of a product to be more than the theoretical mass.

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Correct option is (c). The set of quantum numbers is permissible for an electrons in an atom is n = 2, l=1, m=0, s= + 1/2.

There are total of four quantum numbers are used to describe completely the movement of each electron within an atom. The combination of all the quantum numbers in an atom is described by a wave function. Each of the electron in an atom has a unique set of quantum numbers. Quantum numbers can be used to determine the electron configuration of an atom and the probable location of the electrons of an atom. It is used to understand other characteristics of atoms such as ionization energy and the atomic radius. It describes the values of conserved quantities in the dynamics of a quantum system.

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The correct question is,

Which of the following sets of quantum numbers is permissible for an electrons in an atom?

A. n=1, l=1, m=0, s =+ 1/2

B. n=3, =1, m=2, s= - 1/2

C. n=2, l=1, m=0, s= + 1/2

D. n=2, l=0, m=0, s=1

The volume of the suspension that should be given to an infant weighing 18 lb would be 4.05 mL.

The suspension contains 100 mg in 5 mL.

The recommended dosage is 10 mg per kg body weight.

Weight of infant = 18 lb

1 lb = 0.45 kg

18 lb = 0.45 x 18

        = 8.1 kg

1 kg body weight = 10 mg

8.1 kg body weight = 10 x 8.1

                               = 81 mg

100 mg = 5 mL

81 mg = 81x5/100

           = 4.05 mL

In other words, the volume of the suspension that should be given to an infant weighing 18 lb would be 4.05 mL.

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An ibuprofen suspension for infants contains 100 mg>5.0 mL suspension. The recommended dose is 10 mg>kg body weight. How many mL of this suspension should be given to an infant weighing 18 lb? (Assume two significant figures.)

The characteristic that viruses have in common with living organisms is viruses contain genetic information in the form of DNA or RNA. The correct option is B.

Viruses are an entity that is not living unless they get a living host, they reproduce on a living host.

Nucleic acid makes up the genetic material (or genome) of all viruses. DNA serves as your genetic material, just like it does in all other cell-based life. Yet, viruses can utilize either RNA or DNA, which are both classes of nucleic acid.

Therefore, the correct option is B. Viruses contain genetic information in the form of DNA or RNA.

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The mass of sodium acetate trihydrate required to make 100ml of a 0. 100 m solution is 82g.

Mass is an intrinsic property of a body. It was customarily accepted to be connected with the amount of issue in an actual body, until the disclosure of the iota and molecule material science. It was tracked down that various molecules and different rudimentary particles, hypothetically with a similar measure of issue, have in any case various masses. Mass in present day physical science has different definitions which are adroitly unmistakable, yet all at once genuinely same. Mass can be tentatively characterized as a proportion of the body's idleness, meaning the protection from speed increase (change of speed) when a net power is applied.[1] The item's mass likewise decides the strength of its gravitational fascination with different bodies.

We know that Molarity=number of mole of solute /volume of any solution(solvent) in ml.

Here,we have volume of solution=100ml

also molarity(concentration)=0.100M

Also number of moles of solute=mass of solute/atomic weight of solute.

We know that atomic weight of  sodium acetate trihydarte=82g

So,0.1=(x/82) / 100

=>0.1×82×100=x

=>x=82g

Hence,required mass of sodium acetate trihydrate is 82g.

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No, it is not true that the effect of a catalyst on a chemical reaction is to react with product, effectively removing it and shifting the equilibrium to the right.

A catalyst is a substance that increases the rate of a chemical reaction by lowering the activation energy required for the reaction to occur. It achieves this by providing an alternative reaction pathway with a lower activation energy. The catalyst itself is not consumed in the reaction and is therefore not considered a reactant or a product.

A catalyst does not shift the equilibrium of a chemical reaction, but it can help the reaction reach equilibrium more quickly. Once the reaction reaches equilibrium, the catalyst can speed up the rate of the forward and reverse reactions equally, keeping the concentrations of reactants and products constant.

In summary, the function of a catalyst is to increase the rate of a chemical reaction without being consumed itself and does not affect the position of equilibrium.

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The experimental criterion is to be used to measure the rates of bromination of the hydrocarbons in this experiment is "color change". Option 3 is correct.

Bromination of hydrocarbons involves adding bromine to the hydrocarbon, which results in a color change. Bromine is a reddish-brown liquid, and when it reacts with a hydrocarbon, the color of the mixture fades as the bromine is consumed. The rate of bromination can be determined by measuring the color change over time.

In this experiment, the hydrocarbons can be mixed with a solution of bromine in an organic solvent such as chloroform, and the reaction can be monitored by measuring the color change using a spectrophotometer or by visual observation. The rate of reaction can be determined by measuring the time taken for the color to fade, or by measuring the decrease in absorbance of the bromine solution over time.

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Atoms are the basic building blocks of matter, and since atoms are indestructible, the matter they comprise of is conserved.

We use moles when determining amounts of reactants and products in a reaction because moles allow us to express amounts of substances in terms of the number of atoms or molecules present.

What is molecules?
Molecules are the smallest units of a chemical compound that can exist on its own. They are made up of two or more atoms bonded to each other, forming a unique chemical structure. Molecules are the building blocks of all matter, and they can be found in nature as well as in artificially created compounds. Molecules can be simple or complex, and they can range in size from a few atoms to millions of atoms. They interact with each other, giving rise to chemical reactions. Molecules are essential to life, and understanding how they interact is essential to understanding chemistry.

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Interphase is the longest stage of the cell cycle.The mitotic phase, also known as the M phase, is the shortest stage of the cell cycle.

The longest phase of the cell cycle is interphase, which is further subdivided into G1 (Gap 1), S (Synthesis), and G2 (Gap 2). The cell develops, copies its DNA, and gets ready to divide during interphase. Cellular activity and growth occur during the G1 phase, DNA replication takes place during the S phase, and cell expansion and preparation for cell division occur during the G2 phase.

The shortest phase of the cell cycle is the mitotic phase, sometimes referred to as the M phase. The cell splits its cytoplasm and nucleus to create two daughter cells during this phase. The two main steps of the M phase are mitosis (nuclear division) and cytokinesis (cytoplasmic division). Mitosis entails the division of cells.

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138.908g of H3PO3 would be produced from the complete reaction of 93.2 grams P2O3. 110 gram of P2O3 goes in the green box.

The term mole is defined as the amount of substance of a system which contains as many elementary entities.

One mole of any substance is equal to 6.023 × 10²³ units of that substance such as atoms, molecules, or ions. The number 6.023 × 10²³ is called as Avogadro's number or Avogadro's constant.

In first  step we have to calculate  the  number  of  moles  of  P2O3   reacted

mole = mass  divided  by  RFM

RFM  of  P2O3 = 110

moles are = 93.2/110

= 0.847moles

Therefore, the  reacting  ratio  of  P2O3 to H3PO3   is  1:2  moles  of  H3PO4 = 0.847  x 2  

= 1.694moles

mass = moles  x  RFM  of  H3PO3

1.694  x 82

= 138.908g

Thus, 138.908g of H3PO3 would be produced from the complete reaction of 93.2 grams P2O3.

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The helium Lewis dot structure  is as follows :

   He :

The helium is denoted by the symbol He.  The Helium, belongs to the the  noble gases in the Group 8, it has the only two valence electrons in its valence shell and the first orbit will have the only those two electrons. The electrons are will be represented as the two lone pair with the dots in the Lewis symbol. The lewis structure of the helium is as follows :

   He :

In the lewis or the electron dot structures, the number of the valence electrons for the element is represented by the dots. In the periodic table, the valence electrons will have the highest level of the energy.

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The study of variation and inheritance is called genetics.  "Inheritance being defined as a technique through which the qualities and attributes are passed

The term 'Inheritance' comes a contraction of the word "Inherit" that means, "to inherit any trait, attributes or traits from family". Therefore, "Inheritance being defined as a technique through which the qualities and attributes of the super class or even other derived classes are passed down to the sub or child class.

It also has the ability to take characteristics first from child class and use them in other derived classes." The study of variation and inheritance is called genetics.

Therefore, the study of variation and inheritance is called genetics.

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You would need to take 1864 mL of concentrated hydrochloric acid to prepare 2.80 L of 0.540 M HCl.

To calculate the amount of concentrated hydrochloric acid required, we need to find the number of moles of hydrochloric acid in the final solution and then work backwards to find the amount of concentrated solution required.

The number of moles of hydrochloric acid in the final solution can be calculated as follows:

We know that the concentrated hydrochloric acid is 37.0% HCl by mass and has a density of 1.20 g/mL, so we can calculate the number of moles of HCl in one milliliter of the concentrated solution as follows:

Therefore, to obtain 1.50 moles of HCl, we would need 1.50 moles / 0.0124 moles/mL = 121 mL of the concentrated solution. However, we want to prepare 2.80 L of the final solution, so we would need

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Complete Question:

Hydrochloric acid is usually purchased in a concentrated form that is 37.0% HCl by mass and has a density of 1.20 g/mL. How much concentrated solution would you take to prepare 2.80 L of 0.540 M HCl by mixing with water?

Answer: 12

Explanation: the hcf of 24 and 36 is 12 because the common multiples they both have are 2*2*3 which is equal to 12

The balanced chemical reaction is 2NH3(g) + 5/2 O2 (g) → 2NO (g) + 3H2O (l). A reaction can be balanced by making the atoms equal on both sides of the reaction.

A chemical reaction is said to be a balanced chemical reaction if it have the same number and type of each atom on both sides of the equation. The coefficients in a balanced reaction must be the simplest whole number ratio. Mass is always conserved in a chemical reactions. The chemical reaction is a process in which one or more substances are changed into one or more new substances. In the balanced reaction the atoms in the reactant and the product are equal. Reactants are the starting materials in a reaction. Products are the materials present at the end of a reaction.

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