Which statement correctly describes a physical change? involves breaking and creating chemical bonds but not changing a phase
B. may involve a change in phase but does not involve a change in the molecular structure
OC. may involve converting two or more substances into new substances
D. involves changes at the molecular level
involves energy transfer and change in color

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

What is the ph of a solution that has a hydrogen ion concentration of 1.0 * 10 -9 m?

Which substance has non polar covalent bonds