Carbon-hydrogen-oxygen compound

Figure 18 shows a similar plot with one nitrogen compound (aniline) and a series of carbon-hydrogen-oxygen compounds of various structures. Only n-decane has been represented by a curve, since the other compounds fall closely around it. The aniline s six carbon atoms make it join the carbon compounds in areas of negligible nitrogen response. 

A carbon-hydrogen-oxygen compound, MW = 90 g, is analyzed and found to be 40.0% carbon, 6.7% hydrogen, and 53.3% oxygen. What is the formula of this compound ... 

A key concept in using this procedure is mass balance, which goes back to the reason that we always work with balanced chemical equations. That is, for every mole of H2O observed from combustion, there must have been two moles of H atoms in the unknown carbon-hydrogen (or carbon-hydrogen-oxygen) compound. Similarly, for every mole of GO2 observed, there must have been one mole of carbon in the unknown compound. 

Calculate the percent composition and determine the molecular formula and the empirical formula for the carbon-hydrogen-oxygen compound that results when 30.21 g of carbon, 40.24 g of oxygen, and 5.08 g of hydrogen are reacted to produce a product with a molar mass of 180.18 g. 

Vitamin C is essential for the prevention of scurvy. Combustion of a 0.2000 g sample of this carbon-hydrogen-oxygen compound yields 0.2998 g CO2 and 0.0819 g H2O. What are the percent composition and the empirical formula of vitamin C ... 

Diethylene glycol, used to de-ice aircraft, is a carbon-hydrogen-oxygen compound with 45.27% C and 9.50% H by mass. What is its empirical formula ... 

Pflra-cresol (p-cresol) is used as a disinfectant and in the manufacture of herbicides. A 0.4039 g sample of this carbon-hydrogen-oxygen compound yields 1.1518 g CO2 and 0.2694 g H2O in combustion analysis. Its molecular mass is 108.1 u. For p-cresol, determine its (a) mass percent composition (b) empirical formula (c) molecular formula. 

Writing and Balancing an Equation The Combustion of a Carbon-Hydrogen-Oxygen Compound... 

We deduce the formula of triethylene glycol from the molecular model. (Refer to the color scheme given on the inside back cover.) We see 6 C atoms (black), 4 O atoms (red), and 14 H atoms. The formula is C Hj O. When a carbon-hydrogen-oxygen compound is burned in excess oxygen, Oj, the products are COj and H2O. 

To determine an enthalpy change with Hess s law, we need to combine the appropriate chemical equations. A good starting point is to write chemical equations for the given combustion reactions based on one mole of the indicated reactant. Recall (see page 114) that the products of the combustion of carbon-hydrogen-oxygen compounds are C02(g) and H20(l). 

For compounds containing carbon, hydrogen, oxygen, nitrogen halogens and sulphur. If the compound to be analysed contains sulphur in addition to the elements considered above, then oxides of sulphur will be formed, and a new... 

Animal metaboHsm is based on the reactions of oxygen and organic compounds containing carbon, hydrogen, oxygen, and nitrogen and other heteroatoms. Enzymes catalyze these biochemical oxidations, which are accompHshed at about 30—40°C and frequendy proceed stepwise to produce... 

Hexachlorophene, a compound made up of atoms of carbon, hydrogen, chlorine, and oxygen, is an ingredient in germicidal soaps. Combustion of a 1.000-g sample yields 1.407 g of carbon dioxide, 0.134 g of water, and 0.523 g of chlorine gas. What are the mass percents of carbon, hydrogen, oxygen, and chlorine in hexachlorophene ... 

The positive-ion Cl spectrum, using ammonia as a reagent gas, of an analyte containing carbon, hydrogen, oxygen and two nitrogen atoms, has a molecular species at m/z 222. What is the molecular weight of the compound Involved ... 

Q7. Propose a structure from Spectra 15.10-15.13. The compound is known to be a free base and is composed of only carbon, hydrogen, oxygen and nitrogen. It has a molecular weight of 267. To further complicate matters, the compound was extracted into CDCI3 solution from D20/sodium carbonate so that no exchangeable protons can be observed. 

The determination of the carbon-hydrogen-oxygen content of a compound by combustion analysis involves realizing that all of the carbon has formed carbon dioxide, all of the hydrogen has formed water, and the amount of oxygen present in the original compound must be determined by difference. 

E. J. Prosen. Combustion in a Bomb of Compounds Containing, Carbon, Hydrogen, Oxygen, and Nitrogen. In Experimental Thermochemistry, vol. 1 F. D. Rossini, Ed. Interscience New York, 1956 chapter 6. 

The complex biochemical paths in organisms offer many ways to fractionate isotopes by both kinetic and equilibrium processes. It is therefore expected, and is observed, that the different carbon, hydrogen, oxygen and nitrogen atoms in organic residues show compound and atom-site specific isotope fractionations... 

Compounds are burnt in the flame producing ions and thus an increase in current between the jet and the collector. Detects carbon/hydrogen-containing compounds. Insensitive to carbon atoms attached to oxygen, nitrogen or chlorine. In combination with capillary GC it may detect as low as 100 pg-10 ng. Wide range of linear response ca 10 ... 

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