Table A: Enthalpy of Formation Values for Various Substances
Student Guide (continued)

Substance
Hf (kJ/mol)
NH3(g)
–46.11
NO2(g)
+33.18
CH4(g)
–74.81
C2H4(g)
+52.26
C2H6(g)
–84.68
C3H8(g)
–103.85
C3H6(g)
+20.42
CO2(g)
–393.51
H2O(g)
–241.82
CH3OH(l)
–238.86
Table B: Enthalpy of Formation of Reactants and Products
Substance
Hf (kJ/mol)

Which element is the least metallic between cadmium, silver, zinc, or iron?

An object displaces 652 ml of water. the volume of the object is: 0.652 cm³ 6.52 cm³ 65.2 cm³ 652 cm³

Two people each hold the end of a rope and create waves by moving their arms up and down. this wave is best classified as a transverse wave because a) both the rope particles and the wave are moving in the same direction. b) the wave is moving up and down as the particles of the rope move horizontally. c) the wave is moving horizontally as the particles of the rope move up and down. eliminate d) the wave is moving in a parallel direction with the motion of the person's arms.