Chemistry concerning biology

Question 1

atom is made up of?

Answer 1

neutrons, protons, and electrons.

Question 2

molecules are groups of?

Answer 2

2 or more atoms held together by a chemical bond. Compounds are a type of molecule with multiple different atoms

Question 3

chemical bonds are created by?

Answer 3

Electron interaction

Question 4

electronegativity?

Answer 4

ability of an atom to attract electrons

Question 5

3 bond types?

Answer 5

ionic, covalent, and hydrogen

Question 6

two types of covalent bonds?

Answer 6

nonpolar and polar

Question 7

ionic bonds

Answer 7

transfer of electrons from one atom to another (different electronegativities)

Question 8

covalent bonds?

Answer 8

electrons are shared between atome (similar electronegativities)- can be single, double, or triple. Two types of covalent bonds: nonpolar and polar

Question 9

Nonpolar bond

Answer 9

type of covalent bond. equal sharing of electrons (identical electronegativity)

Question 10

Polar bond

Answer 10

type of covalent bond. Unequal sharing of electrons (different electronegativity and formation of a dipole)

Question 11

hydrogenbond bond

Answer 11

weak bond between molecules with a hydrogen attached to a highly electronegative atom and is attracted to a negative charge on another molecule (F, O, N)

Question 12

What are the 5 properties of water?

Answer 12

1) excellent solvent
2) high heat capacity
3) ice floats
4) cohesion/surface tension
5) adhesion

Question 13

Explain how water is a excellent solvent?

Answer 13

dipoles of H2O break up charged ionic molecules

Question 14

Explain how water has a high heat capacity

Answer 14

heat capacity is the degree in which a substance changes temp in response to gain/loss of heat. The temp of large water bodies are very stable in response to temp changes of surrounding air; must add larger amount of energy to warm up water. High heat of vaporization as well

Question 15

Explain how water lets ice float

Answer 15

water expands as it freezes, becomes less dense than its liquid form. H-bonds become rigid and form a crystal that keeps molecules separated

Question 16

Explain how water has cohesion/surface tension

Answer 16

attraction between LIKE substances due to H-bonds; the strong cohesion between H2O molecules produces a high surface tension

Question 17

Explain how water has adhesion

Answer 17

attraction of UNLIKE substances (wet finger and flip pages). Gives capillary action: ability of liquid to flow without external forcres (even against gravity)