Medium of Life and Properties of Water

Flashcards covering lecture notes on water as the medium of life, enzyme activity, polarity, hydrogen bonding, and extraplanetary origins of water.

In the context of solutions, how are solutes and solvents defined?

Solutes are dissolved substances, while a solvent is a dissolving substance.

What are enzymes and how does temperature affect their collisions?

Enzymes are proteins made of amino acids. Increasing temperature causes more collisions, whereas when water freezes, there are no collisions.

What is the optimum temperature for enzyme activity according to the notes?

The optimum temperature for enzyme activity is $37^\text{ Temp}$.

According to section Al.1.2, how are hydrogen bonds formed in water?

Hydrogen bonds are a force resulting from polar covalent bonds in water.

How does the charge of a polar molecule differ from that of a charged particle?

A polar molecule is net neutral with uneven charge, whereas a charged particle has a net positive or negative charge due to a full loss or gain of electrons.

Which bonds in water molecules are intramolecular versus intermolecular?

Covalent bonds are intramolecular, and hydrogen bonds are intermolecular.

What processes occur in the xylem as a result of hydrogen bonding?

Cohesion, adhesion, and capillary action.

According to section Al.1.7, what points support and counter the asteroid origin of $H_2O$?

Work indicates early asteroids carried significant $H_2O$. Counters state that asteroids hit Earth every $20\text{m}$ years and current day measurements for $H_2O$ on asteroids are low.

What allows Earth to retain $H_2O$ according to section Al.1.7?

$H_2O$ is retained by gravity and the Habitable Zone (Goldilocks zone).