The chemical synthesis of some sulfuric acid is found to require 14.2 mol of sulfur, S. How many sulfur atoms would this be.

Asample of radium-226 will decay 1/4 of its original amount after 3200years. what is the half-life of radium-226?

The lattice enthalpy (formation of ionic solid from ions in the gas phase) for agcl(s) is -916 kj/mol and the hydration enthalpy (dissolution of gaseous ions into water) is -850 kj/mol. how much heat (in joules) is involved in forming 1l of saturated agcl solution (1.8 × 10-4 g / 100 ml water) by dissolving agcl(s)? assume solution volume does not change much upon dissolution. the equations are given below. ag+(g) + cl−(g) æ agcl(s)

Which of the following is a physical change? a.burning a piece of wood b.sawing a piece of wood in half c.rust forming on an iron fence d.a copper roof changing color from orange to green