We can also use the equation for enthalpy change for physical phase changes. Consider the phase change H2O (l) → H2O (g). Calculate ΔHrxn.

How many inner shell electrons does an iodine atom contain?

Which of the following observations would indicate that a material is a pure substance? It does not dissolve in water. It changes color after heating. It cannot be physically broken down into different types of atoms.

Based on the location of nitrogen (N) on the periodic table how many additional electrons does a nitrogen atom need in its valence shell to satisfy the octect rule when it forms bonds

Which is a spectator ion in the reaction between AgNO3 (aq) and KCl (aq) ? A) Cl - (aq) B) NO3 - (aq) C) Ag + (aq) D) OH - (aq)

The electrical current in a circuit is measured in which of the following units. volts resistance amperes pressure

According to periodic trend, which of the following most likely has the highest ionization energy? Na Al Si Ar

Which substances are products of a fermentation reaction? 1. water and carbon dioxide 2. alcohol and carbon dioxide 3. soap and glycerol 4. ester and water

Which particles determines the name of the element?

A rod shaped organism with no nucleus commonly found in Garbage will most likely belong to which kingdom

3. piece of metal is heated to 100.0"C and placed into of water in a coffee cup calorimeter. Initially, the temperature of the water the calorimeter was 23.1C.