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A student needs to analyze an unknown sample to determine the percent composition of three compounds present in it. The student conducts a combustion reaction to determine the percent of carbon and hydrogen in the sample. The remaining residue is then dissolved in water and the solution is titrated with a standardized silver nitrate solution to determine the chloride

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To solve this problem, we need more information about the unknown sample, such as the mass of the sample, the mass of carbon and hydrogen obtained after the combustion reaction, and the volume and concentration of the silver nitrate solution used in the titration. However, I can guide you through the steps to calculate the percent composition of each compound once you have this information.1. Determine the mass of carbon and hydrogen:After the combustion reaction, you should have the mass of carbon and hydrogen obtained. Let's assume the mass of carbon is m_C and the mass of hydrogen is m_H.2. Calculate the mass of the residue:Subtract the mass of carbon and hydrogen from the total mass of the unknown sample. Let's assume the total mass of the sample is m_sample. The mass of the residue  which contains the chloride ions  can be calculated as follows:m_residue = m_sample -  m_C + m_H 3. Determine the moles of chloride ions:From the titration, you should have the volume  V  and concentration  C  of the silver nitrate solution used. Calculate the moles of chloride ions  n_Cl  using the stoichiometry of the reaction between silver nitrate and chloride ions  1:1 ratio :n_Cl = V * C4. Calculate the mass of chloride ions:To find the mass of chloride ions, multiply the moles of chloride ions by the molar mass of chloride  35.45 g/mol :m_Cl = n_Cl * 35.455. Calculate the mass of the third compound:Subtract the mass of chloride ions from the mass of the residue to find the mass of the third compound:m_third_compound = m_residue - m_Cl6. Calculate the percent composition of each compound:Now that you have the mass of each compound, you can calculate the percent composition of each compound in the unknown sample:% Carbon =  m_C / m_sample  * 100% Hydrogen =  m_H / m_sample  * 100% Chloride =  m_Cl / m_sample  * 100% Third compound =  m_third_compound / m_sample  * 100These percentages should add up to 100%.

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