If the atoms that are bonding have identical electronegativities, then it's a completely nonpolar covalent bond. This doesn't happen in the real world unless the two atoms are of the same element. In a practical sense, any two elements with an electronegativity difference less than 0.3 is considered to be nonpolar covalent.
As the difference between the atoms increases, the covalent bond becomes increasingly polar. At a polarity difference of 1.7 (this changes depending on who you ask) we consider it no longer to be a covalent bond and to be the electrostatic interactions characteristic in an ionic compound.
Just so you know, you shouldn't take these values as exact. ALL interactions between adjacent atoms involve some sharing of electrons, no matter how big the difference in electronegativity. Sure, you wouldn't expect much sharing in KF, but there's a little sharing of electrons anyway. There's certainly no big cutoff that happens at a difference of 1.7 Pauling Electronegativity units.
Answer:
chloroplast is the organelle
Ebola is a deadly virus that tricks the body into damaging its own blood vessels. It originated near the ebola river when some animals probably bit someone or someone went into the river and got the virus inside of them through the nose, mouth, ears, open wounds, or other areas. The only way you can spread it is by getting one's body fluids that is infected with ebola (such as spit, mucus, or other fluids that come from the body), on somebody and the fluid somehow works its way into the body.
Answer:
Pneumococcal polysaccharide vaccine
Explanation:
This is a liquid vaccine, and these types of vaccines should not be frozen, because if they do they lose their potency and no longer protect the individual from infections. In fact when these types off vaccines are frozen they can cause local reactions such as sterile abscesses.
