Technician a says that aluminum should be repaired in a separate area from steel. Technician b says that a vacuum attachment should be used when sanding aluminum. Who is right?.

18. use the activity series to predict whether the following synthesis reaction will occur. write the chemical equations for the reaction if it's predicted to occur. (s) + o2(g) -> *note: it is possible.*

The big bang nucleosynthesis theory states that elements were produced in the first few minutes of the big bang while elements have their origins in the interiors of stars, forming much later in the history of the universe.

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