A sample of wood that originally contained 100 grams of carbon-14 now contains only 25 grams of carbon-14. approximately how many years ago was this sample part of a living tree?

How do insects or small animals become preserved in amber

Some amount of water is evaporated from a 2.0 L, 0.2 M NaI solution, to from a 1.0 L solution. The molar mass of NaI is 150 g/mol. What is the final concentration of NaI solution in

Convert 11.03 moles of calcium nitrate to grams.

Write the chemical formula for a compound that is made of an element from group 1 and an element from group 17

How much heat is needed to melt 45.00 g of ice at 0°C if the latent heat of fusion of water is 333.7 J/g? 288.7 J 378.7 J 14,220 J 15,020 J

The three major groups p On the periodic table are the

Which of the following has the greatest mass, in grams? a. 1 atom of lead (Pb) b. 0.5 mol copper (Cu) atoms c. 0.3 mol gold (Au) atoms d. 25 atoms of mercury (Hg)

Which one is not a sedimentery rock a.) sandstone b.) limestone c.) quartz d. (coal

Which group is more reactive than the alkaline earth metals?

Why do you not want any of the water on the outside of the test tube to drip off into the calorimeter?