The half life for the decay of carbon-14 is 5.73 x 10 years. suppose the activity due to the radioactive decay of the carbon-14 in a tiny sample of an artifact made of wood from an archeological dig is measured to be 19. bq. the activity in a similar-sized sample of fresh wood is measured to be 20. bq. calculate the age of the artifact. round your answer to 2 significant digits. years x 5 ?

Order the following from smallest to largest atom, electron, quark, proton, neutron, molecule, nucleus

Why is the bond angle in a water molecule less than the bond angle of methane? a. the central oxygen atom in water has two lone pairs of electrons, whereas the central carbon atom in methane has no lone pairs. b. the central hydrogen atom in water has one lone pair of electrons, whereas the central carbon atom in methane has two lone pairs. c. the central oxygen atom in water has four lone pairs of electrons, whereas the central carbon atom in methane has only one lone pair. d. the central oxygen atom exerts more repulsive force on surrounding atoms than the central carbon atom in methane does. reset next

Which change in temperature is the smallest? a change of 1 thomson degree a change of 1 kelvin degree a change of 1 fahrenheit degree a change of 1 celsius degree