Each element has a certain affinity for electrons known as electronegativity. The higher the electronegativity of an element the more affinity it has to pull electrons towards itself. Because many elements do not have similar electronegativity values, their ability to pull electrons to themselves is also dissimilar.
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flourine has an electronegativity of about 4.0, the highest on the Periodic Table and carbon has about 2.4. Because of the difference in values, electron density is pulled towards the fourine atom because it has a greater affinity to pull electrons.
The shape of a molecule also has a lot to do with the expected polarity of the bond. Electron pulling is represented by vectors which have both direction and magnitude. If there is a case in that all the vectors are of equal magnitude but of opposite direction such that the force is cancelled out then the overall polarity is practically nonexistent. CF4 is non polar because all four flourines pull electron density towards them with the same magnitude but opposite direction, effectively canceling the polarity. This phenomenom can also be observed on symmetrical alkenes of the trans variety
H2O is a polar covalent molecule. It forms covalent bonds between the hydrogen and oxygen atoms, but due to the unequal sharing of electrons, the oxygen atom becomes slightly negative while the hydrogen atoms become slightly positive, leading to a polar molecule.
Electronegativity= the ability of an atom to attract a pair of electrons in a covalent bondSo the electrons will be drawn towards the more electronegative atom, causing this atom to become slightly negative (δ-) and the less electronegative atom to become slightly positive (δ+), so the bond is polarised.
when atoms share electrons, the positive nucleus of each atom is attracted to the shared negative electrons. the pull between the positive and negative charges is the force that keeps these atoms joined......hope this hepls :)
A positive ion can become a neutral atom by gaining electrons. When a positive ion gains one or more electrons, it becomes neutral because the negative charge of the electron(s) cancels out the positive charge of the ion.
Non-metals typically become negative ions when they form ions because they gain electrons to achieve a full outer electron shell. This results in a negative charge due to the extra electrons present in the ion.
When the difference of the electronegativity between the atoms is significant the molecule is less or more polar.
H2O is a polar covalent molecule. It forms covalent bonds between the hydrogen and oxygen atoms, but due to the unequal sharing of electrons, the oxygen atom becomes slightly negative while the hydrogen atoms become slightly positive, leading to a polar molecule.
The pull of one atom is slightly stronger,or weaker than the pull of the other atom.
In a covalent bond, atoms share electrons. If one atom is more electronegative, it can pull the shared electrons closer to itself, giving it a slightly negative charge, while the other atom, with less electronegativity, can become slightly positive as the electrons are closer to the more electronegative atom. This creates a dipole moment in the molecule.
A polar covalent compound is a compound consisting of molecules which have regions of positive and negative charge due to the covalent bonding between atoms. The atom with a greater charged nucleus ( atoms with greater proton number) will attract the shared electrons causing them to move closer to the nucleus which will make this slightly negatively charged due to the negative electrons. The atom which the shared electrons has moved away from ( atoms with smaller proton number) will become slightly positively charged.
Electronegativity= the ability of an atom to attract a pair of electrons in a covalent bondSo the electrons will be drawn towards the more electronegative atom, causing this atom to become slightly negative (δ-) and the less electronegative atom to become slightly positive (δ+), so the bond is polarised.
Part of the Molecule will be slightly negative and the other slightly positive. One example is water. The oxygen atom hogs the electrons leaving the oxygen slightly negative and the hydrogen slightly positive. This makes the water molecules slightly "sticky" and the water molecules clump together. If this didn't happen then water would boil at -120 deg C intead of +100 degrees.
Negative times negative equals positive.
Yes. A negative subtracted by a negative is a positive. Just remember that two like signs become a positive sign, and two unlike signs become a negative sign.
When we lose something negative you become positive.
You divide the negative number by a positive number for it to stay positive. And you divide the negative number by a negative number for it to become positive.
When you multiply any number by a negative number you reverse its sign. So positive numbers become negative, and negative numbers become positive. That is the meaning of negative multiplication; it is reversal. This is similar to the way that adding a negative number has the same effect as subtracting a positive number. Negative is the opposite of positive.