Which of the following chemical reactions is a single displacement reaction? A. 2Na + O2
Na o
B. Pb(NO3)2 + 2KBr → PbBr2 + 2KNO3
C. 2Fe(OH)3 Fe2O3 + 3H20
D. 2A1 + 3Zn(NO3)2 2AI(NO3)3 + 3Zn

Which of the following statements is not true? • a. covalent compounds have low melting and boiling points. • ob. covalent bonds between atoms of a compound are relatively weak compared to bonds between molecules. • c. covalent bonds occur between nonmetals. • d. covalent compounds are often gases or liquids.

Two atoms interact with each other as shown by the equation. complete the equation by filling in the missing parts. 1 2 3 4 5 h he li

What is the mass of sodium in 3 moles of sodium chloride