Calculate the mass of oxygen that combines with 20.4g of magnesium to form 34.0g of magnesium oxide

Which statement about sound is not true? a. air particles travel with sound waves. b. sound waves cannot travel through a vacuum. c. sound waves exist even if no one hears them. d. air particles vibrate along the path of a sound wave.

Which characteristic of water it form droplets? a. low specific heat b. nonpolar structure c. high surface tension d. ability to dissolve substances

Consider the story you just read. all but one of the choices below indicate that something is living.