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Flashcards in ch 2 Deck (52)
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1

solid

definite shape and volume

2

liquid

definite volume, changeable shape

3

gas

changeable shape and volume

4

96% of body weight results from what elements?

carbon
hydrogen
oxygen
nitrogen

5

which elements make up 3.9% of the body?

phosphorus
sulfur
magnesium
potassium
sodium
iodine
calcium
chlorine
iron

6

Trace elements

required in minute amounts
found as part of enzymes

7

Atomic mass unit of protons neutrons and electrons

protons= 1 amu
neutrons= 1 amu
electrons= 1/2000 amu

8

why are atoms electrically neutral

because #p= #e

9

mass #

p & n

10

atomic weight

average of mass #s of all isotopes

11

isotope

atoms with same #p but different #n

12

whats the octet rule

except for 1st shell (which is full with 2e) atoms interact to have 8 valence e

13

what do ionic compunds form

crystals instead of individual molecules. ex: NaCl (sodium chloride)

14

what do covalent bonds produce

molecules.
-single covalent bond: share pair of e. (H-H)
-double covalent bond: share 2 pairs of e. (O=C=O)

15

hydrogen bonds

-alone they're too weak to bind atoms together, however, when combined theyr'e very strong
-surface tension in H2O
-intramolecular bonds (gives molecule 3-D shape)

16

dissociation

separation of ions in ionic compound by polar water molecules
-dissociated ions: electrolytes
-nonelectrolytes: molecules don't associate in water

17

dehydration reaction

synthesis; water is a product

18

Hydrolysis reaction

decomposition; uses water

19

definition of energy

capacity to do work (put matter into motion)

20

types of energy

potential, kinetic, mechanical, chemical, electrical, radiant or electromagnetic

21

What factors influence the rate of chemical reactions

concentration
temperature
catalysts
particle size

22

Acids

release H+
proton donors
more H+ than OH-
pH

23

Neutral

pH of 7.0
= # of H+ and OH-

24

Bases

releases OH-
proton acceptors
pH > 7.0 (7.01- 14.00)
alkaline solutions
fewer H+ than OH-

25

buffered solution

added H+ bound by buffer, pH change is small

26

no buffer

add acid: increase of H+ and decrease in pH

27

Inorganic chemistry

non-C containing substances
except CO, CO2, HCO3-

28

organic chemistry

substances contain C, covalently bonded, often large
-Usually C-C or C-H bonding

29

what are the 4 properties of water

stabilizes body temp
protection
chemical reaction
transport

30

examples of carbohydrates and what they contain

monosaccharides- glucose, fructose
disaccharides- sucrose, lactose
polysaccharides- starch, glycogen