When copper (cu) and oxygen (o) combine, two different compounds are formed. the first compound contains 88.8% copper by mass, and the second compound contains 79.9% copper by mass. (note: assume a 100-gram sample of each compound.) (a) show that cu and o combine with each other in conformity with the law of multiple proportions. the small whole number ratio of the mass of cu per gram of o in the first compound to the mass of cu per gram of o in the second compound equals : 1. this ratio indicates that cu and o with each other in conformity with the law of multiple proportions.

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