Carbon dating of small bits of charcoal used in cave paintings has determined that some of the paintings are from 10000 to 30000 y old. carbon-14 has a half-life of 5730 y. in a 1μg-sample of carbon from a live tree, the activity of carbon-14 is 6.4μci. if researchers determine that 1μg of charcoal from a prehistoric cave painting in france has an activity of 0.80 μci, what is the age of the painting?

How many grams of magnesium metal will react completely with 8.3 liters of 5.5m hcl? show all work

Consider a culture medium on which only gram-positive organisms such as staphylococcus aureus colonies can grow due to an elevated nacl level. a yellow halo surrounds the growth, indicating the bacterium fermented a sugar in the medium, decreasing the ph as a result and changing the color of a ph indicator chemical. this type of medium would be referred to as a differential and enrichment culture.

Steam reforming of methane ( ch4) produces "synthesis gas," a mixture of carbon monoxide gas and hydrogen gas, which is the starting point for many important industrial chemical syntheses. an industrial chemist studying this reaction fills a 1.5 l flask with 3.5 atm of methane gas and 1.3 atm of water vapor at 43.0°c. he then raises the temperature, and when the mixture has come to equilibrium measures the partial pressure of carbon monoxide gas to be 1 .0 atm. calculate the pressure equilibrium constant for the steam reforming of methane at the final temperature of the mixture. round your answer to 2 significant digits.