A discharge lamp produces 5.0 J of energy per second in the blue region of the spectrum. How many photons of blue (470 nm) light would the lamp generate if it were left on for 8.5 s?

If 34.2 grams of lithium react with excess water, how many liters of hydrogen gas can be produced at 299 kelvin and 1.21 atmospheres? 2 li (s) + 2 h2o (l) yields 2 lioh (aq) + h2 (g)

Calculate the molar mass of aluminum oxide (al2o3). express your answer to four significant figures.

If blood contains 150g of hemoglobin per liter of blood, how much hemoglobin would be contained in 10 ml of blood