- A 300g sample of CaCO3 was heated until 10 L of CO2 was collected at 50°C and 742 torr. What percentage of the CaCO, had
decomposed? (Atomic weights (g/mol): C=12, 0=16, Ca=40)
A. 6.84%
B. 9.10%
C. 12.3%
D. 15.8%

The bond energy for the van der waals bond between two helium atoms is 7.9×10−4ev. assuming that the average kinetic energy of a helium atom is (3/2)kbt, at what temperature is the average kinetic energy equal to the bond energy between two helium atoms

Which of the following are sources of revenue for media companies? a. direct sales to producers b.advertising and subscriptions c. online purchase d. capital investments

How many moles of sulfuric acid (h2so4) are needed to react completely with 6.8 moles of lithium hydroxide (lioh)? 2lioh + h2so4 → li2so4 + 2h2o a. 3.4 mol h2so4b. 6.8 mol h2so4 c. 10.2 mol h2so4 d. 13.6 mol h2so4