A sample of fluorine-18 is found to have an activity of 980 disintegrations per second (dps). After 8.0 hours the activity has decreased to 45 dps. What is the half-life, in years, for the decay of fluorine-18

10. translate each of the following chemical equations into a sentence. a. 2 zns(s) + 3 o2(g) -> 2 zno(s) + 2 so2(g) b. cah2(s) + 2 h2o(l) -> ca(oh)2 (aq) + 2 h2(g)

When 225mg of anthracene, c14h10(s), was burned in a bomb calorimeter the temperature rose by 1.75k. calculate the calorimeter constant. by how much will the temperature rise when 125mg of phenol, c6h5oh(s), is burned in the calorimeter under the same conditions? (δch< (c14h10,s)=–7061 kj mol−1.)

In one or two grammatically correct sentences, write a definition for the term molecule geometry