Water Basics & Polarity
What kind of molecule has a positive end and a negative end?
polar molecule
What is cohesion?
Attraction between water molecules.
What two parts make up a solution?
Solute and solvent.
What does the pH scale measure?
The concentration of hydrogen ions (Hâș).
Keeping things like temperature, water level, and pH steady inside the body is called what?
Homeostasis.
What type of bond holds the two hydrogen atoms and one oxygen atom together within a single water molecule?
Covalent bond â the atoms share electrons.
What is adhesion?
Attraction between water and other materials.
In salt water, what is the solute and what is the solvent?
Solute = salt; Solvent = water.
What numbers on the pH scale represent acids?
0 â 6.
What is a substance that prevents sudden changes in pH.?
buffer
What kind of bond holds one water molecule to another?
Hydrogen bond.
What property is responsible for: Water drops forming beads on a surface or raindrops on a leaf.
cohesion
How can you tell if a mixture is a suspension instead of a solution?
A suspension has visible particles that settle or make the liquid look cloudy; a solution looks clear and evenly mixed.
What numbers on the pH scale represent bases?
8 â 14.
Why does your mouth taste sour right after drinking soda?
Soda is acidic â the acid temporarily lowers the pH in your mouth.
What property of water is responsible for keeping body temperature and climates stable?
High Heat Capacity
What allows lets water stick to the inside of a straw or plant stem
Adhesion
Which mixture forms when soil is stirred into waterâsolution or suspension?
Suspension
Which has more Hâș ions: lemon juice (pH 2) or soap (pH 10)?
Lemon juice â itâs more acidic.
Why does milk help when your stomach feels too acidic after eating spicy food?
Milk is slightly basic, so it neutralizes some of the acid.
How does waterâs polarity make it a good solvent?
The positive and negative ends attract other charged or polar molecules, helping them dissolve.
What property is responsible for cohesion of water molecules at the surface forming a âskinâ?
surface tension
Why is blood considered both a solution and a suspension?
Blood plasma is a solution (dissolved materials), and red and white blood cells are suspended in it.
How many times more acidic is a substance with pH 3 than one with pH 6?
1,000 times (10 Ă 10 Ă 10).
Why is it important that your stomach stays acidic but your blood stays near neutral?
Acid helps digest food, but blood must stay neutral so cells can function safely.