How is Hess's law used to measure enthalpy of a desired reaction? A. The enthalpy is obtained from the enthalpy of an intermediate
step.
B. The enthalpy is determined from the enthalpy of similar reactions.
C. The enthalpy from the final equation in a series of reactions is
used
D. Intermediate equations with known enthalpies are added together.

Which statement describes covalent bases? they have hydroxide ions. they produce hydrogen ions. they are often amines. they are named the same as ionic compounds.

Cryolite, na3alf6(s), an ore used in the production of aluminum, can be synthesized using aluminum oxide. start this question by first balance the chemical equation.1.) balance the equation: - alo3(s)+naoh(l)+hf(> na3alf6+h2o(g). 2.) if 17.5 kilograms of al2o3(s), 51.4 kilograms of naoh(l), and 51.4 kilograms of hf(g) react completely, how many kilograms of cryolite will be produced? 3.)which reactants will be in excess, (al2o3, naoh, or hf) 4.)what is the total mass of the excess reactants left over after the reaction is complete in kg?

Light waves are as they pass through the