A sample of rock contains 6.14 × 10^–4 g of Rb-87 and 3.51 × 10^–5 g of Sr-87. Calculate the age of the rock. (The half-life of the β decay of Rb-87 is 4.7 × 10^10 y.)

Write a hypothesis that answers the lesson question, “while observing a chemical reaction, how can you tell which reactant is limiting? ” hypothesis: if a substance is the limiting reactant, then . . because . .

How many moles of ccl4 are in 3.55l

Which of these describes how heat is transferred by convection* a. sunlight travels through space without the aid of fluids or solids. b. warm air rises and takes the heat with it, eventually, it cools and sinks c. air at the equator rises and sinks at the poles. d. air molecules touch the warm ground, heating them up *not conduction