CHEMISTRY;ESPECIALY FUNCTION IN BREAKING BONDS
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Both of the above are correct.  Xylene is a benzene ring on which two of the hydrogens have been replace with methyl groups.  They can be in three configurations: ortho, where the two methyls are on adjacent carbons in the benzene ring; meta, where they are separated by one carbon; and para, where the methyl groups are diametrically opposite each other.\n\nThe most common use that we experience each day is that xylenes are used as the solvents in permanent magic markers.
131976
Because the bonds between the atoms are very strong, it takes a lot of energy to break them.
69856
C, remember that the electron loses and gets energy several times through the chain.
208669
The oxygen is used for the oxidation of glucose molecules, so that they are broken down and release the energy that we need for the metabolic activities inside our body.\nFirst the glucose molecule is acted upon by enzymes which break it into 2 'chains'. The 6 carbon atoms in the chains then react with oxygen to form CO2; and simultaneously an enzyme dehydrogenase removes hydrogen atoms from the glucose molecule which then react with oxygen to form water. \nC6H1206 + 6O2 ----> 6CO2 + 6H20 + energy
354735
It is not a reaction because the bond formed is ionic, not covalent.  Extraction is a better term for the process you are describing.
501054
The smaller the atom, the harder it is to remove an electron from it. This is the measure of an atom's ionisation energy.\n\nThe smaller an atom (with the exception of the noble gases),  the more likely it is to accept an additional electron. This is a measure of its electron affinity.\n\nBoth of these concepts factor in when determining whether bonding between two atoms is covalent or ionic.
607405
You're forgetting something with your reasoning here.  It is true that in chemistry, creating bonds releases energy, but how do you get particles to create bonds between?  You have to break other bonds, which requires energy.  If catabolic pathways release energy when they break down complex molecules, the amount of energy it takes to break those bonds is less than the amount of energy released when new bonds are formed from the broken-up parts.
413185
Determining structure of molecules.\nIonic structures- The Alkali metal halides are ionic compounds e.g NaCl. Na has a positive charge whereas Cl has a negative charge.\n\nMolecular solids- are held by weak bonds called Van Der waals forces. \n\nMacromolecular structures or giant molecular- have covalent bonds between atoms, these bind all the atoms into a giant molecule e.g Diamond
373452
It's:\n\nSum of bond enthalpies of product - Sum of bond enthalpies of reactants
518669
1)electron ...(also negative meson)\n2)the atom is the basic (many atoms make molecule and so on)\n3)polymer (the most famous are protiens)
504930
The role of the enzyme is to stabilize the transition state enzyme-substrate complex so that reaction conditions are favorable.  Without the enzyme, many reactions in our bodies would not take place. The enzyme serves as a catalyst for the reaction.
341571
Okay, first off balance the equation...\n\nCH4(g) + 2H20(g) ---> CO2(g) + 4H2(g)\n\nDrawing the structures lets you see what bonds are being broken and which ones are being formed (a little hard to do here).  To find the enthalpy of the reaction add the bond enthalpies of the bonds you're breaking and then subtract from that the sum of the bond enthalpies that you're forming.\n\nSo.... you have 4 C-H bonds to break, 4 O-H bonds to break, and you're forming 2 C-O double bonds and 4 H-H bonds.  I looked these up in my book, so they may vary slightly...\n\n[(4  C-H bonds * 413 kj/mol)] + (4  O-H bonds * 463 kj/mol)] - [(2  C-O double bonds * 799 kj/mol) + (4  H-H bonds * 436 kj/mol)] = +162 kJ/mol
527750
(c) Hydrogen and oxygen atoms of adjacent molecules.\n\nHydrogen bonds are formed between an electronegative atom (i.e., O, N, F), and a hydrogen bonded to an electronegative atom.\n\nTherefore, the oxygen of one water molecule interacts with the hydrogen in an adjacent water molecule.
310266
See if this article has a diagram\n\nhttp://jchemed.chem.wisc.edu/Journal/Issues/1999/Apr/abs542.html
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B\n\nStrong bonds requires more energy to break and therefore releases more energy when formed.\n\nSo when enthalpy(heat) is lowered you need something that eats more energy than it creates.
538366
The ligand will accomodate electrons from the ligands, forming dative bonds.\n\nThe sub-shell also ceases into two groups of orbitals.  One group will be at a higher energy level as compared with the other.  The difference in energy level is acounted by the strength of the ligand, in other words, by its polarising power.  The stronger the ligand, the greater is the energy difference between the two groups of orbitals.
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Molecular.\n\nAnother word for it is 'covalent.'