why are atoms of bromine so reactive?
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All of the Halogens (Br is a member) need only gain one electron to become stable. Its' diameter is on the smallish side for an atom of this size so it easy to capture and hold one electron.\n\nThe Alkali Metals on the other side complement the Halogens.\n\nGet an "A".
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I'm guessing by 'the atomic model' of the atom, you mean the correct model. It was proposed by bohr, and is essentially the same as the rutherford model except that the electrons are held into shells. Note the wikipedia article below.\nas for the reactivity of different groups, you need to read about valence electrons. They're the number of electrons in the incomplete (outermost) electron shell -- group 1 has 1 valence electron, group 17 has one MISSING valence electron. Atoms are more stable when they have 'full' shells, and no incomplete ones, so the group 1 atoms will try to 'give away' their extra electron, while the group 17 atom will try and 'take away' one more electron to complete its shell.
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HBrO4---\n\nThe compound perbromic acid, HBrO4, is an oxygen acid of bromine. Perbromic acid is unstable and cannot be formed by displacement of chlorine from perchlorate, as periodates are prepared. The acid was discovered when a sample of radioactive selenate Se*O42- was left to decay. It is a strong acid, and strongly oxidizing, and is the least stable of the halogen(VII) acids. It decomposes rapidly on standing to bromic acid and oxygen, with the evolution of brown bromine vapour.
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each type atoms have different no of proton that definize what atom is it.\ninteligent design. dont even thing about it\nlabs arround the world can make atoms from different atoms thru the process of nuclear fusion or fission. \n\nstability?? u mean in chemical compound, its because the atom bounding theory,  u will study it in chem\nif thats not what u r asking so I don no
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The halogens can be found in column 17 of the Periodic Table.  They are called Group VII because they all have 7 electrons in their outer orbitals.\n\nThe lighter ones (Fluorine & Chlorine) are gases at room temperature.  Bromine is a liquid, while Iodine & Astatine are solids.  All tend to rapidly react by gaining an electron (they are good oxidizers).\n\nThe noble gases can be found in column 18 of the Periodic Table.  They are called Group VIII because they all have 8 electrons in their outer orbitals.\n\nHaving full outer orbitals, the noble gases usually do not react with other elements.  This is why they are sometimes called the Inert Gases.  Several compounds of Xenon and Fluorine and Oxygen have been make and studies, however.
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Well, statistics always govern reactions.  Sometimes the statistics are so much in favor of one product that the others are negligible.  \nRadical reactions (especially on un-functionalized moleculess) are always prone to selectivity problems.  Radicals are so reactive they really don't care what they react with.  The more selective a reactive species is, the more likely a single product outcome is.  It's not "automatic".  Major/minor product mixtures are a reality - you will often ignore them in chem class, but in real life it happens all the time - truly single product reactions are rare.
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It does apply loosely to other halides, but Cl and Fl are considerably more reactive.  Br and especially I have more significant steric hindrances to overcome.\n\nSee the link below to see where Markownikoff gort his idea.
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If it existed, it would be boron pentafluoride, but as far as I know, this is not a stable molecule.\n\nAre you sure you don't mean BrF5 (bromine pentafluoride), which does exist as a stable molecule?
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As you know, benzene is rather unreactive. Its conjugate pi system is entirely impervious to conventional nucleophilic and electrophilic attack. For example, you can react HBr with it forever, and you won't get Bromobenzene.\n\nWhat you have to do is to find a way to "pump up" the electrophile that is being used to attack the ring. When you run a bromination, you do:\n\nPh + Br2 ---> (w/ FeBr3 catalyst) PhBr\n\nAn Iron bromide catalyst works as a Lewis Acid to create Br+ in situ. This Br+ is electrophilic enough to promote the benzene's pi electrons to attack, forming the sigma complex and leading to bromobenzene.\n\nNitration works the same way. NO3 is not a strong enough nucleophile to promote the reaction. The H2SO4 is a stronger acid than NO3 and it protonates it, yielding NO2+ (HSO4 + H20 as spectators). This NO2+, called nitronium, is enough to cause the nitration of the benzene ring.
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if it forms a 2- ion it is from the Chalcogen (group V1(A) or 16) family (Oxygen, Sulphur, ...).  The two bonds between two Oxygen atoms are Covalent.  It has 6 valence electrons and takes two to complete the valence shell (noble configuration).\n\nThe reaction of X with Sodium (Na) will require twice as many Na atoms as Sodium only has 1 valent electron to give (to make the Na+ ion)\n\nSo\n\n2Na + X -> Na2X which in a polar solvent (e.g. water) will become 2Na+ +X2- \n\nFYI, the Halogens are Fluorine, Chlorine etc and only have one single space left to take an electron to reach Noble configuration hence they form singly charged anions F-, Cl-...
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1) Highest electrotronegativity.In Pauling scale flourine's electronegativity is 4. Consequently F atom has a strong tendency to attract electrons from the other elements.Fluorine thus compels the other elements to combine with it.Due to its strong electronegativity & small size Fluorine has a strong tendency to accept electrons from other atoms or ions. As a result it oxidises all other substances.\n\n\n2) The bond dissociation energy of F2 is very low, due to this Fluorine easily comes to reactive atomic state. The low bond dissociation energy can be explained in the following ways\n\na] since F atom do not contain any d orbital d(pi)-p(pi) bond in F2 molecule is not possible( which is possible in other halogens). This cause was proposed by Mulliken.\n\nb] According to Coulsan, The F-F bond distance in F2 molecule is  least because of the small size of F atom.The non-bonding electrons in 2p subshell of one F atom exerts great repulsion on that of another F atom. Which causes easy bond cleavage.\n\nc] the bond existing between two F atoms is a single covalent bond. So the bond dissociation energy is minimum.\n\n3) The bond energy of Fluorine in Fluoride compound is very high & so it requires a great amount of energy to break this bond, consequently the tendency to form Fluoride compounds is much higher.
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The H will attach to the Carbon atom which is already bonded to other hydrogen atoms, in this case, to carbon,2.  Bromine will bond to the other carbon, hence carbon,1.\n\nAns: d.
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Diatomic, but not all diatomic gases are Halogens
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Different chemical composition, one has a reaction the other doesn't..☺
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Bromine is in it's ionic form for both reactions (solubility rules)\nSo you have the equation:\nFe+3 + Na(s) > Fe(s) + Na+\n\nHalf Reactions:\nFe+3 + 3e- > Fe(s)\nNa > Na+ + 1e-\n\nYou'll need 3 sodiums to take in the 3 electrons given off from the Iron.\n\nMaking it:\n\nNet-Ionic: Fe+3 + 3Na(s) > Fe(s) + 3Na+\nStandard: FeBr3 + 3Na(s) > Fe(s) + 3NaBr
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Mendeleev's work in developing a periodic table showed that similarities among elements appeared with a certain regularity. As chemists developed ways to learn about the structure of atoms, it became apparent that this regularity could be explained on the basis of the arrangement of the electrons in atoms, especially the number of electrons most distant from the nucleus.\n\nThe arrangement of electrons helps explain the formation of different kinds of chemical bonds. Some bonds result from the donation of one or more electrons from one atom to another atom in the compound.Bonds of this type are called ionic, and compounds with bonds of this type are called ionic compounds. The component parts of ionic compounds are called ions. For example, sodium chloride is an ionic compound formed when electrons from sodium atoms move to chlorine atoms.The sodium atom is converted into a sodium ion with a positive charge.The chlorine atom is converted into a chloride ion with a negative charge.\n\nCovalent bonds are formed when electrons from two or more atoms are shared. Compounds formed in this way are called covalent compounds. Carbon tetrachloride is an example of a covalent compound. Four chlorine atoms surround a carbon atom. Each chlorine atom shares one of its electrons with the carbon; and, conversely, the carbon atom shares its electrons with the chlorine atoms.\n\nIn metals, the atoms are closely packed together in rows and layers. These rows and layers explain why metals are easy to bend. The loosely-bound outer electrons in metal are shared among many atoms, creating a ìseaî of negative charges holding the metal ions in place. This is called metallic bonding. The type of bonding, whether ionic, covalent, or metallic, determines the properties and the ways in which we use substances!\n\nChemical reactions occur when the atoms are taken apart or rearranged. Energy is conserved in such reactions;that is, the energy of the reactants is equal to the energy of the products.\n\nChemical reactions proceed at different rates. Some, such as the rusting of iron, proceed slowly. Others, such as the burning of methane gas, proceed rapidly. Temperature, surface area, air pressure, and the presence of moisture or catalysts are all conditions that affect the rates of chemical reactions. Catalysts are substances that increase the rate of a reaction but are not changed themselves when the reactions are complete.\n\nHuman understanding of these principles of chemistry has enabled us to make hundreds of thousands of useful products, which enhance our lives greatly.
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Presuming that bromine is getting reduced to Br(-) and bisulfite is getting oxidized to sulfate (not including the spectator sodium ion):\n\nReduction half-reaction\nBr2 + 2e ---->  2Br(-)\n\nOxidation half reaction\nHSO3(-) + H2O ----->  SO4(2-) + 2e + 3H(+)\n\nOverall Reaction:\nBr2 + HSO3(-) + H2O ---->  SO4(2-) + 2Br(-) + 3H(+)