A museum wants to store their valuable documents in cases that contain a gas that will protect the documents. The museum director should choose Choose... = chlorine gas, oxygen gas, a noble gas, a halogen.
She should not choose one of the other gases because they are too
Choose... = expensive, reactive, smelly, unreactive.

Identify which properties could correspond to solids, plasmas, or both. maintain a unique shape. collide infrequently with other particles. have very high velocities. conduct electricity. protons. have a low temperature. has long-range order.

Given that 1 mi = 1760 yd, determine what conver- sion factor is appropriate to convert 1849 yd to miles; to convert 2.781 mi to yards.

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