The half-life of f-20 is 11.4 seconds. when there are 200 atoms of f-20 in a sample, a scientist starts a stopwatch. the scientist stops the stopwatch at 34.2 seconds; there are atoms of f-20 remaining.

6what is the importance of water on earth? a) it keeps the top layer of the geosphere cool b) it allows life to exist c) it provides ice at the poles d) it creates earth's blue color from space

The chemical equation below shows the reaction of sodium (na) and chlorine (cl) to form sodium chloride (nacl). 2na + cl2 → 2nacl in this equation, which of the following is a reactant? i. sodium ii. chlorine iii. sodium chloride

Draw the aromatic compound toluene (methylbenzene). show all hydrogen atoms, including those on the ring.