When 1 mole of propane (C3H8) is burned at a constant pressure 2221 kJ of energy is released as heat. Calculate Delta H for a process in which 25.0 g of propane is burned at a constant pressure

Correct relationship between molecular formula and empirical formula

For a research project, a student decided to test the effect of the lead(ii) ion (pb2+) on the ability of salmon eggs to hatch. this ion was obtainable from the water‐soluble salt, lead(ii) nitrate, which the student decided to make by the following reaction. pbo(s) + 2 hno3(aq) → pb(no3)2(aq) + h2o losses of product for various reasons were expected, and a yield of 86.0% was expected. in order to have 5.00 g of product at this yield, how many grams of pbo should be reacted? (assume that sufficient nitric acid, hno3, would be used.)

How many atomic mass units are equal to 1.672×10−24 g of protons?