Iron ore exists as Fe2O3. In order to remove the oxygen and generate pure iron, the oxygen must be transferred to another molecule. Carbon monoxide can be mixed with iron ore and carbon dioxide is generated. Carbon monoxide is produced in the combustion of carbon with limited oxygen. Calculate the value of ΔS° for the oxidation of carbon to carbon monoxide, 2C (s, graphite) + O2 (g) --> 2CO (g)

A. +179.4 J/mol K

B. +408.6 J/mol K

C. -408.6 J/mol K

D. +395.8 J/mol K

Ionic compounds are made of ions, and yet the overall charge of an ionic compound is neutral. why?

Which of the dna typing techniques do you think you would choose if you had to analyze a dna sample? why?

The atomic radius of sodium is 186 pm and of chlorine is 100 pm. the ionic radius for na+ is 102 pm and for cl– is 181 pm. in going from na to cl in period 3, why does the atomic radius decrease while the ionic radius increases? a. the inner electrons in the sodium cation shield its valence electrons more effectively than the inner electrons in the chloride anion do. b. the inner electrons shield the valence electrons more effectively in the chlorine atom than in the chloride anion. c. the outermost electrons in chloride experience a smaller effective nuclear charge than those in the sodium cation do. d. the outermost electrons in chloride experience a larger effective nuclear charge than those in the sodium cation do. e. monatomic ions are bigger than the atoms from which they are formed.