A combustible substance cannot catch fire or burn as long as its temperature is lower than its ignition temperature. Please explain this with a suitable activity. (PLEASE DON'T WASTE MY POINTS)

Which of the following molecules is polar? c3h7oh c2h5cooh

Give one example of a pure (exact) number and of an estimated (measured) number.

What is the difference between covalent bonds and ionic bonds? covalent bonds involve the sharing of electrons between atoms; ionic bonds involve the electrical attraction between charged atoms. covalent bonds involve the transfer of electrons between charged atoms; ionic bonds involve the sharing of electrons between atoms. covalent bonds involve the sharing of pairs of electrons between atoms; ionic bonds involve the sharing of single electrons between atoms. covalent bonds involve the sharing of electrons between atoms; ionic bonds involve the sharing of protons between charged atoms.