Se enfría un bloque de aluminio de los 500° C a los 40° C. ¿Cuál es la masa del bloque si pierde 90 kcal de calor?​

Asample of the male sex hormone testosterone, c19h28o2, contains 3.88×10^21 atoms of hydrogen.(a) how many atoms of carbon does it contain? (b) how many molecules of testosterone does it contain? (c) how many moles of testosterone does it contain? (d) what is the mass of this sample in grams?

Achemist 16 drop copper metal from copper chloride solution. the chemist place is 0.50 g of aluminum foil in a solution containing 0.75 g of copper (ii) chloride. a single replacement reaction takes place. which statement explains the maximum amount of copper that the chemist can extract using this reaction?

Ajet plane is speeding down the runway during takeoff. air resistance is not negligible. identify the forces on the jet.