Water (H 2 O). Why water exists and why is it important Water’s unusual properties Hydrogen bonding and polarity Liquid state Cohesion Solvent Water and solutions Hierarchy theory and the emergent properties of water. Take Home Message.
0oC to 100oC
CompoundChemical FormulaFreeze VaporRange(oC) (oC) (oC)
Water H2O 0 100 100
Ammonia NH3 -78 -33 45
Methane CH4 -182 -164 18
H2O H+ + OH-
H2O + H+ H3O+ (hydronium ion)
Substance A has a pH of 2 and Substance B has a pH of 3. This means that ____.
A. Substance A is more basic than Substance B
B. Substance B is more acidic than Substance A
C. Substance A is 10 times more acidic than substance B
D. Substance B is 10 times more acidic than substance A
A deep lake in Minnesota is covered with ice. What is the water temperature at the bottom of the lake?
In the summer in Virginia, pond water temperature is very warm (~30 0C). In the fall, the drop in night time air temperature results in surface water temperature falling (e.g., 20 0C). What would you expect to happen in small ponds as the surface water temperature is cooler than the water temperature at the bottom of the pond (~30 0C)?
How does ocean water in proximity to continents affect the climate of the adjoining land mass? Explain your analysis based on the physical and chemical properties of water.
In the search for life on other planets and in other solar systems, why is the presence and/or absence of water regarded as one of the cardinal indicators of the possibility of life?