14.) An extremely toxic pesticide was spilled in a pond. It is known that this pesticide degrades to harmless products in water via a first-order reaction with a half-life of 12 hours. How long will it take for the
concentration of the pesticide in this pond to reach 1% of its initial value? Assume that the temperature is
constant and no water is lost or gained.

The two naturally occurring isotopes of chlorine are 35cl (34.969 amu, 75.77%) and 37cl (36.966 amu, 24.23%). the two naturally occurring isotopes of bromine are 79br (78.918 rm amu, 50.69%) and 81br (80.916 amu, 49.31%). chlorine and bromine combine to form bromine monochloride, brcl. 1. how many peaks will be present in a mass spectrum for brcl? the four combinations of molecule possible given these four isotopes are: 81br37cl, 81br35cl, 79br37cl, and 79br35cl. 2. what are the masses of the four different brcl molecules? express the masses using six significant figures, in decreasing numeric order (highest to lowest), separated by commas.

How many neutrons does an element have if its atomic number is 50 and its mass number is 166

11) burning your hand when accidentally touching a hot plate is an example of which heat transfer? a. conduction b. convection c. radiation d. none of these