WOD: CAPITULATE kah PICH uh layt) v. Do Now 10/2 10/2 Chapter 2.2: Properties of Water 16 WOD: CAPITULATE kah PICH uh layt) v. to surrender under certain conditions; to give in After continuous bombing, the enemy finally agreed to CAPITULATE. After sending a rose everyday for three weeks, Betty finally CAPITULATED and married Ed.
KEY CONCEPT Water’s unique properties allow life to exist on Earth.
Life depends on hydrogen bonds in water. Water is a polar molecule. Polar molecules have slightly charged regions. O H _ + Nonpolar molecules do not have charged regions. Hydrogen bonds form between slightly positive hydrogen atoms and slightly negative atoms.
Hydrogen bonds are responsible for three important properties of water. high specific heat cohesion adhesion
Many compounds dissolve in water. A solution is formed when one substance dissolves in another. A solution is a homogeneous mixture. Solvents dissolve other substances. Solutes dissolve in a solvent. solution
“Like dissolves like.” Polar solvents dissolve polar solutes. Nonpolar solvents dissolve nonpolar solutes. Polar substances and nonpolar substances generally remain separate.
Some compounds form acids or bases. An acid releases a hydrogen ion when it dissolves in water. high H+ concentration pH less than 7 more acidic stomach acid pH between 1 and 3
A base removes hydrogen ions from a solution. low H+ concentration pH greater than 7 bile pH between 8 and 9 more basic
A neutral solution has a pH of 7. pure water pH 7
Water is essential for life Water is essential for life. Its special properties make water the single most important molecule in plant life. Which of the following properties of water enables it to move from the roots to the leaves of plants? A. Water expands as it freezes. B. Water is an excellent solvent. C. Water exhibits cohesive behavior. D. Water is able to moderate temperature.
Large bodies of water, such as lakes and oceans, do not quickly fluctuate in temperature. What is the reason for this phenomenon? A. Water is an acid. B. Water is a versatile solvent. C. Water has a high heat capacity. D. Water acts as a buffer.
Water is often called the "universal solvent" because many substances can be dissolved in water. What property of water allows it to be such a versatile solvent? A. purity B. polarity and cohesion C. high heat capacity D. expansion upon freezing