Water Flashcards
What is the structure of water?
H20
What type of bond holds the atoms within a water molecule together?
Polar Covalent bond + hydrogen bond
What is polarity?
electronegative charges that lead to dipole movement, unequal sharing of electrons
What is a hydrogen bond and how does it relate to water molecules?
an electrostatic attraction between a hydrogen atom in one polar molecule (as of water) and a small electronegative atom (as of oxygen, nitrogen, or fluorine) in usually another molecule of the same or a different polar substance.
What is cohesion
The ability for water molecules to cling to eachother
What is adhesion?
The ability of water molecules to cling onto other polar molecules.
What is surface tension?
A light skin surface of a liquid as it cling to each other and is exposed to air. For liquid to shrink to minimum surface area
What is high heat capacity?
Water’s ability to absorb and retain/keep heat.
What is evaporative cooling? (evap cool)
the use of evaporated water to cool hot air. converting liquid into vapor using thermal energy in the air, therefore cooling down.
What does it mean that water is the universal solvent?
Water is generally able to dissolve most substances than any other liquid.
Why is water less dense as a solid than as a liquid?
In ice crystals, their hydrogen bonds link them together like acrobats, stacked one on top of the other, with their arms and legs outstretched. This provides more space between the molecules in the crystal structure of ice than the molecules of liquid water. As a result, ice is less dense than the liquid form. Has a more structured form, unlike water which is close together and breaks and re-forms.
What is pH? How is it measured?
Measure of hydrogen ion concentration of a solution, measured by 10^-(number on scale). Used to specify acidity and basicity. Also measured from 0-14.
What are acids?
Acids are substances that dissociate in water releasing [H+] ions. acidity depends on how fully it dissociates in water.
What are bases?
Substances that either take up hydrogen ions [H+] or release [OH-] hydroxide ions.
What are buffers?
A chemical or combination of chemicals that keeps pH normal. Occurs naturally and readily takes up excess H+ or OH- as the concentration changes.
