If 3.0 grams of strontium-90 in a rock sample remained in 1989, approximately how many grams of strontium-90 were present in the original rock sample in 1933?

A chunk of aluminum weighing 19.7 grams and originally at 98.01 °C is dropped into an insulated cup containing 81.3 grams of water at 21.05 °C. Assuming that all of the heat is transferred to the water, the final temperature of the water is

If there's a jar that contains helium gas. What would happen if the lid of the jar was removed?

If two atoms have different atomic number. Are they the same element or an isotope?

Give the net ionic equation for the reaction (if any) that occurs when aqueous solutions of Al (C2H3O2) 3 and LiNO3 are mixed.

Flammability is an example of what? A. chemical property B. physical property C. dangerous substance D. atomic bond

Gases and liquids will both expand to fill their container. True False ... ?

Which of the following best explains why electrometallurgy is a useful process in many industries? A.) Electrometallurgy can etch permanent marks and designs into the surfaces of metal products. B.

Your TLC results for ortho-hydroxyacetophenone versus para-hydroxyacteophenone will indicate that one compound is significantly less polar than the other.

A box contains equal amounts of helium, argon, and krypton (all gases) at 25 ∘c. part a consider the temperatures, masses, average velocities, and average kinetic energy of the three kinds of gas in the mixture.

Why are coastal zones productive?