Review the mass and size of an atom. A typical hydrogen atom, for example, has a mass of 1.66 x 10-24 g. Imagine how big a number we would need to describe the number of atoms in a real-life sample of an element. Could we somehow measure or handle a dozen or a ream of atoms? Explain.

The answer is probably c. xylem

Hbr dissociates to form h+ and br-ca(oh)2 dissociates to form ca2+ and 2oh-the h+ and oh- react to form waterassuming the reactants are dissolved in water, the net reaction is h+ + oh- —> h2oif you’re asked to show all components of the reaction, the complete reaction is 2hbr + ca(oh)2 —> cabr2 + 2h2o