if the pka of an acid (hv) is 8.0, how would you prepare a 0.05 m buffer of ph = 8.6, given a bottle of 1.0 m hcl, 1.0 m naoh, and solid acid?

Method 1a, Karl Fischer reagent preparation,  (based on the USP quantities) the theoretical amount of water (in mg) equivalent to 1 mL KFR is 5.331 mg.

Karl Fischer is a method of determining trace amounts of water in a sample, it is widely used in the pharmaceutical and chemical industries. In this method, the Karl Fischer reagent is used to react with water. It is essential to prepare the reagent with high precision to obtain accurate results. One of the methods of Karl Fischer reagent preparation is Method 1a, it involves mixing methanol, sulfur dioxide, and pyridine in a specific ratio. The reagent is then standardized using a standard water solution.

The USP defines the quantities of these reagents for the preparation of Karl Fischer reagent. To calculate the theoretical amount of water equivalent to 1 mL of KFR, the amount of water the reagent can react with should be determined. According to the USP, 1 mL of Karl Fischer reagent can react with 5.331 mg of water. Hence, the theoretical amount of water equivalent to 1 mL of KFR is 5.331 mg.

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combination reaction,decombination reaction,displacement reaction,decombinatio reaction,neutrilizatio reaction

The given reactions are combination reaction, decomposition reaction, neutralization reaction, displacement reaction and double displacement reaction.

A displacement reaction is a chemical process during which a one more reactive element being replaced from its compound by a less reactive element.

When A combination reaction occurs when one or more elements or compounds react together to generate a new chemical. Equations of the following kind are used to depict such reactions.

X+ Y→XY

6) \(Fe}(s)+3{O}_{2}(g)\) → \(2{Fe}_{2} {O}_{3}(s)\), this reaction is a kind of combination reaction reaction.

7) \({Zn}_{2}(s)+2 {HCl} (aq)\) → \({ZnCl}_{2}(a q)+{H}_{2}(g)\)

This reaction is a kind of displacement reaction.

8) \({MgCO}_{3}(a q)+2 {HCl}(a q)\)  →\({MgCl}_{2}(a q)+{H}_{2} {O}(l)+{CO}_{2}(g)\).

This reaction is a kind of combustion reaction.

9) \({NiCl}_{2}(s)\) → \({Ni}(s)+{Cl}_{2}(g)\).

This reaction is a kind of decomposition reaction.

10) \({C}(s)+6 {H}_{2}(g)+{O}_{2}(g)\) → \(2 C}_{2} {H}_{6} {O}(s)\).

This reaction is a kind of combination reaction.

11) \($\mathrm{C}_{12} \mathrm{H}_{22} \mathrm{O}_{11}(s) \rightarrow 12 \mathrm{C}(s)+11 \mathrm{H}_{2} \mathrm{O}(\mathrm{g})$\) .

This reaction is a kind of dissociation reaction.

12) \($2 \mathrm{LiI}(a q)+\mathrm{Pb}\left(\mathrm{NO}_{3}\right)_{2}(a q) \rightarrow 2 \mathrm{LiNO}_{3}(a q)+\mathrm{PbI}_{2}(s)$\).

This reaction is a kind of double displacement reaction.

13) \($\mathrm{CdCO}_{3}(s) \rightarrow \mathrm{CdO}(s)+\mathrm{CO}_{2}(g)$\).

This reaction is a kind of decomposition reaction

14) \($\mathrm{Cl}_{2}(g)+2 \mathrm{KBr}(a q) \rightarrow 2 \mathrm{KCl}(a q)+\mathrm{Br}_{2}(g)$\).

This reaction is a kind of single displacement reaction.

15) \($\mathrm{BaCl}_{2}(a q)+2 \mathrm{KIO}_{3}(a q) \rightarrow \mathrm{Ba}\left(\mathrm{IO}_{3}\right)_{2}(s)+2 \mathrm{KCl}(a q)$\).

This reaction is kind of double displacement reaction.

16) \($2 \mathrm{Mg}(s)+\mathrm{O} 2(\mathrm{~g}) \rightarrow 2 \mathrm{MgO}(s)$\).

This reaction is a kind of combination reaction.

17) \(AgNO_{3} (aq) +KI(aq)\) →\(KI(aq) + KNO_{3}(aq)\).

This reaction is a kind of double displacement reaction.

18) \($2 \mathrm{Li}(s)+\mathrm{H}_{2} \mathrm{O}(b) \rightarrow 2 \mathrm{LiOH}(a q)+\mathrm{H}_{2}(g)$\).

This reaction is a kind of single displacement reaction.

19) \($\mathrm{C}(\mathrm{s})+\mathrm{O}_{2}(\mathrm{~g}) \rightarrow \mathrm{CO}_{2}(\mathrm{~g})$\).

This reaction is a kind of combination reaction.

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\(▪▪▪▪▪▪▪▪▪▪▪▪▪  {\huge\mathfrak{Answer}}▪▪▪▪▪▪▪▪▪▪▪▪▪▪\)

The stratosphere is cold except in its upper regions where Ozone is located.

Answer:c

Explanation:

Each water molecule is joined to Four other water molecules by Hydrogen bonds

As can be seen in the illustration on page 1 of the activity titled "The Polarity of Water" a water molecule is joined to four other water molecules by hydrogen bonds.

A hydrogen bond is an attraction between an electronegative atom carrying a single pair of electrons—the hydrogen bond acceptor—and a hydrogen atom that is covalently bonded to a more electronegative "donor" atom or group.

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The phosphate concentration of the unknown sample is 0.002 M

Beer's law, the quantity of power absorbed or transmitted by using a solution is proportional to the solution's molar absorptivity and the awareness of the solute. In easy terms, a greater focused answer absorbs greater light than a more dilute solution does.

C = εa/b

  =  0.285 / 137.2

   = 0.002 M

A sequence of fashionable solutions containing a purple dye was made by diluting an inventory answer and then measuring the percent transmittance of every answer at 505 nm (greenish blue). This wavelength became decided on with the aid of examining its absorption spectrum.

Lambert's law of absorption states that equal elements inside the equal absorbing medium soak up identical fractions of the mild that enters them. If in traversing a path of duration dx the intensity is decreased.

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Note that the diagrammatic representation of all the phases of water is attached accordingly.

The processes involved in the changes between gas, solid, and liquid states of matter are:

The changes between gas, solid, and liquid states can be brought about by altering temperature and/or pressure.

For example, decreasing the temperature and/or increasing the pressure can cause a gas to become a liquid or a solid, while increasing the temperature and/or decreasing the pressure can cause a solid or liquid to become a gas. Other factors such as intermolecular forces and molecular structure can also affect the state of matter.

Note that the four phases of matter are gas, solid, liquid, and plasma. In the gas phase, molecules are far apart and move quickly.

In the solid phase, molecules are tightly packed and vibrate in place. In the liquid phase, molecules are close together and move randomly. Plasma is a high-energy state of matter that consists of ionized particles.

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(A) R_r represents the rate of change of resistance with respect to the radius of the artery, r. The units of R_r are mmHg/mm. A negative value for R_r indicates that an increase in the radius of the artery will result in a decrease in resistance, meaning it becomes easier for blood to flow through the wider artery.

(b) The derivative is zero because the resistance with respect to the radius does not depend on the length of the artery.

(a) To calculate R_L (L, r), we differentiate the equation with respect to L while keeping r constant:

\(R_L(L, r) = d/dL (kL/r^4) = k/r^4\)

R_L represents the rate of change of resistance with respect to the length of the artery, L. The units of R_L are mmHg/cm. A positive value for R_L indicates that an increase in the length of the artery will result in an increase in resistance, meaning it becomes harder for blood to flow through the longer artery.

To calculate R_r (L, r), we differentiate the equation with respect to r while keeping L constant:

\(R_r(L, r) = d/dr (kL/r^4) = -4kL/r^5\)

R_r represents the rate of change of resistance with respect to the radius of the artery, r. The units of R_r are mmHg/mm. A negative value for R_r indicates that an increase in the radius of the artery will result in a decrease in resistance, meaning it becomes easier for blood to flow through the wider artery.

(b) To calculate R_rr (L, r), we differentiate R_r (L, r) with respect to r while keeping L constant:

\(R_rr(L, r) = d/dr (-4kL/r^5) = 20kL/r^6\)

R_rr represents the rate of change of R_r with respect to r. The units of R_rr are mmHg/mm^2. A positive value for R_rr indicates that as the radius of the artery increases, the rate of decrease in resistance increases. In other words, the wider the artery becomes, the easier it is for blood to flow through.

To calculate R_rL (L, r), we differentiate R_r (L, r) with respect to L while keeping r constant:

\(R_rL(L, r) = d/dL (-4kL/r^5) = 0\)

R_rL represents the rate of change of R_r with respect to L. The units of R_rL are mmHg/(cm·mm). The derivative is zero because the resistance with respect to the radius does not depend on the length of the artery. This implies that changes in the length of the artery do not affect the rate of change of resistance with respect to the radius.

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Implementing a new system into an organization module by module is called a Phased Approach.

The "phased approach," as the name implies, is a project planning strategy in which anything new, such as a software solution, is introduced in stages rather than all at once.

Rather than installing and rolling out new software across an entire organization at the same time, older systems/methodologies are gradually replaced. Phased implementation necessitates extensive project planning to determine which software functions should go live first and for which departments.

This process allows you to keep the most critical departments operational while others transition to the new system. However, phasing may not be necessary for every company or project. As software and technology become more complex, however, the phased approach reduces risk and often makes the most business sense.

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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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The rate of the reaction, 2A+B→C, with zeroth order in A and zeroth order in B, and a rate constant of \(k=0.0739 Ms^{−1} , is 0.0739 Ms^{−1}\).

The rate of the reaction can be determined using the rate law equation and the given concentrations of A and B.

The rate law equation for the given reaction is rate =\(k[A]^x[B]^y\), where [A] and [B] represent the concentrations of A and B, respectively, and k is the rate constant.

In this case, the rate law is zeroth order in A and zeroth order in B, which means that the concentrations of A and B do not affect the rate of the reaction. Therefore, x and y in the rate law equation are both zero.

To calculate the rate, substitute the values into the rate law equation:
rate = \(k[A]^x[B]^y\)
    = \(k[0.20M]^0[0.15M]^0\)
    = k

Given that the rate constant k is 0.0739 \(Ms^{-1}\), the rate of the reaction is also 0.0739\(Ms^{−1}\).

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Answer:

How many gallons of water are on earth?

Why does salt water make you sticky and burn our eyes so bad?

Explanation:

These are just a couple questions I came up with just now

I hope that this helps

The  22.25g of the solid precipitate will form when a solution containing 52.897 g of mercury(ii) perchlorate is allowed to react completely with a solution containing 14.334 g of sodium dichromate .

To determine the mass of the solid precipitate formed, we need to find the limiting reactant in the reaction. The reactant that is completely consumed will determine the maximum amount of product that can be formed.

First, we need to determine the moles of each reactant. We can use the molar mass to convert the given masses to moles.

Molar mass of mercury(II) perchlorate (Hg(ClO₄)₂) = 2 * atomic mass of Hg + 8 * atomic mass of Cl + 16 * 4 * atomic mass of O

Molar mass of mercury(II) perchlorate (Hg(ClO₄)₂)= 2 * 200.59 + 8 * 35.45 + 16 * 4 * 16

Molar mass of mercury(II) perchlorate (Hg(ClO₄)₂)= 723.62 g/mol

Moles of (Hg(ClO₄)₂)  = mass / molar mass

Moles of (Hg(ClO₄)₂)  = 52.897 g / 723.62 g/mol

Moles of (Hg(ClO₄)₂) ≈ 0.073 moles

Molar mass of sodium dichromate (Na₂Cr₂O₇) = 2 * atomic mass of Na + 2 * atomic mass of Cr + 7 * atomic mass of O

Molar mass of sodium dichromate (Na₂Cr₂O₇) = 2 * 22.99 + 2 * 52 + 7 * 16

Molar mass of sodium dichromate (Na₂Cr₂O₇) = 261.97 g/mol

Moles of  (Na₂Cr₂O₇) = mass / molar mass

Moles of  (Na₂Cr₂O₇) = 14.334 g / 261.97 g/mol

Moles of  (Na₂Cr₂O₇) ≈ 0.055 moles

The balanced chemical equation for the reaction is:

3 Hg(ClO₄)₂+ Na₂Cr₂O₇ → 3 HgCrO₄ + 2 NaClO₄

From the balanced equation, we can see that the stoichiometric ratio between Hg(ClO₄)₂ and Na₂Cr₂O₇ is 3:1. Therefore, 3 moles of Hg(ClO₄)₂ react with 1 mole of Na₂Cr₂O₇ .

Since the ratio between moles is 3:1, and we have 0.073 moles of Hg(ClO₄)₂and 0.055 moles of Na₂Cr₂O₇ , Na₂Cr₂O₇ is the limiting reactant.

This means that all of the Na₂Cr₂O₇ will be consumed, and we need to calculate the amount of solid precipitate formed based on this limiting reactant.

The molar mass of (mercury(II) chromate) HgCrO₄= atomic mass of Hg + atomic mass of Cr + 4 * atomic mass of O

The molar mass of (mercury(II) chromate) HgCrO₄= 200.59 + 52 + 4 * 16

The molar mass of (mercury(II) chromate) HgCrO₄= 404.59 g/mol

Moles of  HgCrO₄ formed = moles of Na2Cr2O7

Moles of  HgCrO₄ formed= 0.055 moles

Mass of  HgCrO₄formed = moles of  HgCrO₄* molar mass of  HgCrO₄

Mass of  HgCrO₄formed = 0.055 moles * 404.59 g/mol

Mass of  HgCrO₄formed ≈ 22.25 g

The mass of the solid precipitate ( HgCrO₄) that will form is approximately 22.25 grams.

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A student wants to make magnesium chloride, MgCl₂. The student adds magnesium carbonate to hydrochloric acid, HCI.

MgCl₂ = 1 x Mg + 2 x Cl = 24.31 + 2 x 35.45 = 95.21 g/mol

To find the mass of MgCO₃ that reacts to form 0.0200 mol of MgCl₂, we first need to use the balanced equation to determine the mole ratio of MgCO₃ to MgCl₂:

1 mol MgCO₃ : 1 mol MgCl₂

So, 0.0200 mol MgCl₂ will react with 0.0200 mol MgCO₃.

The molar mass of MgCO₃ is:

MgCO₃ = 1 x Mg + 1 x C + 3 x O = 24.31 + 12.01 + 3 x 16.00 = 84.31 g/mol

mass = moles x molar mass = 0.0200 mol x 84.31 g/mol = 1.69 g

To find the mass of HCl that reacts, we can use the stoichiometry again:

1 mol MgCO₃ : 2 mol HCl

So, 0.0200 mol MgCl₂ will react with 0.0400 mol HCl.

The molar mass of HCl is:

HCl = 1 x H + 1 x Cl = 1.01 + 35.45 = 36.46 g/mol

The mass of HCl required is:

mass = moles x molar mass = 0.0400 mol x 36.46 g/mol = 1.46 g

Therefore, the masses of MgCO₃ and HCl that react to form 0.0200 mol of MgCl₂ are 1.69 g and 1.46 g, respectively.

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Answer:

There are three types of periods in the modern periodic table: very short periods, short periods, and long periods.

The difference between very short periods and short periods is the number of elements they contain. Very short periods only contain two elements, while short periods contain eight elements. The difference between short periods and long periods is the number of orbitals that can be occupied by electrons in each period. Short periods can only have electrons in the s- and p-orbitals, while long periods can also have electrons in the d-orbital.

Here is a table summarizing the differences between very short periods, short periods, and long periods:

The correct statement about pericyclic reactions is:

In pericyclic reactions, all bonds are broken and formed in a single step.

Pericyclic reactions are a class of organic reactions characterized by the simultaneous breaking and forming of multiple bonds in a concerted manner, meaning that all bond changes occur in a single step. This is in contrast to stepwise reactions where bonds are broken and formed in separate steps.

In a pericyclic reaction, the reactants rearrange their electrons in a concerted fashion, leading to the formation of new bonds and the breaking of existing bonds. This concerted process occurs through the overlap of molecular orbitals, allowing for the efficient transfer of electrons.

Pericyclic reactions are concerted reactions in which the breaking and forming of bonds occur simultaneously in a single step. They do not involve multiple steps or intermediates. The transition state in a pericyclic reaction is cyclic, not acyclic.

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Answer:

A and D are the answers

Explanation:

the other two don't make sense

The statements C and D are correct, i.e., curly hair have different protein structure from straight hair and curly hair results from a change in the gene.

Proteins are biomolecules made of amino acids. Proteins are very essential to all living things and contributes the body structure. Proteins are mainly up taken through diet and they are the main source of energy.

Hair is made of keratin protein. Keratin makes up our skin and nails too.Curly hair is originating by birth not developing over time. Curly hair is more likely to be occurring through inheritance.

The protein structure the hair follicle is some more bend for curly hair. Curly hair and straight hair originates from different gene traits. The gene type is inherited from the parents.

Hence, for people with curly hair have different protein structure and it result from a change in gene that code for hair structure. Thus options C and D are correct.

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A conjugate acid-base pair is the pair of two compounds which differ by the presence of a proton. An acid will donate protons to a base and become a conjugate base. A base will accept protons and become a conjugate acid.Conjugate acid/base pairs are as follows:H2PO4− and HPO42−H2CO3 and CO32−HCl and Cl−H3O+ and OH−Explanation:

H2PO4− and HPO42−H2PO4− can donate a proton to become HPO42− and the latter can accept a proton to become H2PO4−.H2CO3 and CO32−H2CO3 can donate a proton to become CO32− and the latter can accept a proton to become H2CO3.HCl and Cl−HCl can donate a proton to become Cl− and the latter can accept a proton to become HCl.H3O+ and OH−H3O+ can donate a proton to become OH− and the latter can accept a proton to become H3O+.Therefore, the following are conjugate acid/base pairs:H2PO4− and HPO42−H2CO3 and CO32−HCl and Cl−H3O+ and OH−

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The property of matter that is conserved in chemical reactions and shown by balanced equations is known as the Law of Conservation of Mass. According to this law, mass can neither be created nor destroyed in a chemical reaction; it can only be transformed from one form to another.For instance, when two substances are combined, they react and form a new substance.

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Answer:

Its food for cannibals.

Answer:

K2Cr2O7

Explanation:

Solubility refers to the amount of substance that dissolves in a given mass or volume of solvent. There are several units of solubility applicable in different areas.

Solubility is dependent on temperature. The solubility curve is a graphical representation of the dependence of solubility on temperature for different chemical species.

If we study the solubility curve closely, we will see that K2Cr2O7 has the highest solubility at 100°C. This means that if the trends continue, this substance will also have the highest solubility at 120°C.

Answer: c

Explanation:

Answer: a beating heart,emotions,pain

Explanation:

Answer:Open this pdf if has the answers

Explanation:

Formula

\(\ell=\frac{n h}{2 \pi}\)

\(\ell = angular \: momentum\)

\(n = principal quantum number \\ h = Planck's constant \\ \pi = pi\)

Answer:

+1

Explanation:

if 3.45 grams of magnesium are burned, 1.725 grams of magnesium oxide are produced. The chemical equation for the reaction of magnesium with oxygen is 2MgO.

Magnesium is a chemical element that is highly reactive, meaning that it easily reacts with other substances. When magnesium is burned in the presence of oxygen, it reacts with the oxygen to form magnesium oxide,

The chemical equation for the reaction of magnesium with oxygen is:

2Mg + O2 -> 2MgO

This equation tells us that for every 2 grams of magnesium that react with oxygen, 2 grams of magnesium oxide are produced. Therefore, if 3.45 grams of magnesium are burned, the number of grams of magnesium oxide produced can be calculated as:

3.45 grams Mg / 2 grams Mg/1 gram MgO = 1.725 grams MgO

Therefore, if 3.45 grams of magnesium are burned, 1.725 grams of magnesium oxide are produced.

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The Iupac Name of given three compounds are 3,4,5-trimethylheptane, 2,2,3,3-tetramethylpentane and 2,2- dimethyl-3-ethylpentane.

For (1),

The longest straight chain have 7 carbon compound and having single bond, suffix of this compound is Heptane. Now there are three functional group of methyl there for prefix is trimethyl. Overall the name of compound is 3,4,5-trimethylheptane.

The longest straight chain have 5 carbon compound and having single bond, suffix of this compound is pentane. Now there are four functional group of methyl there for prefix is tetramethyl. Overall the name of compound is 2,2,3,3-tetramethylpentane.

The longest straight chain have 5 carbon compound and having single bond, suffix of this compound is pentane. Now there are three functional group of methyl and ethyl so they write according to alphabetic order. Overall the name of compound is 2,2- dimethyl-3-ethylpentane.

Thus, we concluded that the The Iupac Name of given three compounds are 3,4,5-trimethylheptane, 2,2,3,3-tetramethylpentane and 2,2- dimethyl-3-ethylpentane.

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The Compare and contrast of metallic and ionic bonds is given below.

Ionic and metallic bonds take occur between positive and negative ions, whereas ionic bonds take place between positive ions and electrons. This is the main distinction between the two types of bonds.

Ions, which are made up of a positive and a negative ion, are created when two atoms exchange electrons. Atoms sharing electrons to form a molecule result in covalent bonds. Metal atoms shed their outermost electron to produce positively charged ions, which then form metallic bonds.

Metal ions are attracted to delocalized or free e, forming metallic connections as a result. whereas ionic bonds are created by electron transfer from one atom to another.

Similar to ionic bonds, where the removal of electrons results in the formation of ions, metallic bonds include the removal of electrons to create a sea of electrons.

Later, these electrons are used or shared by each and every atom, and in covalent bonds, two atoms share one electron. Consequently, metallic bonds resemble both ionic and covalent bonds.

Ionic and metallic solids differ significantly in that metallic solids contain metal atoms and free electrons while ionic solids mostly comprise cations and anions.

Additionally, metallic solids feature metallic bonds rather than the electrostatic attraction forces between cations and anions that exist in ionic solids.

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Answer:

hello the options related to your question is missing hence I will give you a general answer as regards to combination of atoms in a chemical reactions

answer :

In a chemical reaction the bonds that are found between the atoms of reactants are broken up and a different/new bonds are formed between the atoms of the various reactants involved in the chemical reaction to produce a new product.   during this process no new atoms are created but new bonds are created  to form a product

Example of such substance where atoms can combine together in a chemical reaction is : Iron sulfide  [ Fe(s) + S(s) → FeS(s) ]

Explanation:

In a chemical reaction the bonds that are found between the atoms of reactants are broken up and a different/new bonds are formed between the atoms of the various reactants involved in the chemical reaction to produce a new product.   during this process no new atoms are created but new bonds are created  

Example of such substance where atoms can combine together in a chemical reaction is : Iron sulfide  [ Fe(s) + S(s) → FeS(s) ]  i.e. combination of Iron atoms and sulfur atoms