Dipole is defined as A. the separation of charges in a nonpolar bond
B. the separation of charges in a polar bond
C. the separation of charges in an ionic bond
D. the separation of charges in a conjugated bond
E. the separation of charges in a dispersion bond

Which compound contains both ionic and covalent bonds? a) hbr b)cbr4 c)nabr d) naoh

Why is the bond angle in a water molecule less than the bond angle of methane? a. the central oxygen atom in water has two lone pairs of electrons, whereas the central carbon atom in methane has no lone pairs. b. the central hydrogen atom in water has one lone pair of electrons, whereas the central carbon atom in methane has two lone pairs. c. the central oxygen atom in water has four lone pairs of electrons, whereas the central carbon atom in methane has only one lone pair. d. the central oxygen atom exerts more repulsive force on surrounding atoms than the central carbon atom in methane does. reset next

Which of the following is an example of physical change not a chemical change? a) a log gives off heat and light as it burns. b) a tree stores energy from the sun in its fruit. c) a penny lost in the grass slowly changes color. d) a water pipe freezes and cracks on a cold night.