Which characteristic best explains the difference in melting behavior of covalent substances and ionic substances? Ionic substan
ces have weaker intermolecular attractions. Ionic substances usually have stronger atomic bonds. Covalent substances have weaker intermolecular attractions. Covalent substances usually have stronger atomic bonds.
Dolphins use a method called echolocation to detect things such as obstacles and prey in the water. If a dolphin swimming in seawater at 25°C sends a 220-dB click with a frequency of 120.0 Hz, and then detects the reflection of the click exactly one-twentieth of a second later, approximately how far away is the object?
