Date post: | 02-Jun-2018 |
Category: |
Documents |
Upload: | nuramirah-hassan |
View: | 237 times |
Download: | 0 times |
of 48
8/10/2019 Chap1 Chang
1/48
Chemistry:
The Study of Change
Chapter 1
Copyright The McGraw-Hill Companies, Inc !ermission re"uired for reproduction or display
PowerPoint Lecture Presentation
by
J. David Robertson
University of Missouri
8/10/2019 Chap1 Chang
2/48
Chemistry: # Science for the $%stCentury
&Health and Medicine
&Sanitation systems
&Surgery with anesthesia
&'accines and anti(iotics
&)nergy and the )n*ironment
&+ossil fuels
&Solar energy
&uclear energy
%%
8/10/2019 Chap1 Chang
3/48
Chemistry: # Science for the $%stCentury
&Materials and Technology
&!olymers, ceramics, li"uid crystals
&oom-temperature superconductors.
&Molecular computing.
&+ood and #griculture
&Genetically modified crops
&/atural0 pesticides
&Speciali1ed fertili1ers
%%
8/10/2019 Chap1 Chang
4/48
The scientific methodis a systematic
approach to research
%2
# lawis a concise statement of a relationship
(etween phenomena that is always the same
under the same conditions
# hypothesis is a tentati*e e3planation for aset of o(ser*ations
tested modified
8/10/2019 Chap1 Chang
5/48
CHEMISTRY
The study of MATTER and the
changes that matter undergoes
and the energyassociated with
the changes.
MATTER is anything thatoccupies space and has mass.
8/10/2019 Chap1 Chang
6/48
% Matteris anything that occupies space and
has mass
$ # substanceis a form of matter that has a
definite composition and distinct properties
Chemistryis the study of matter and the
changes it undergoes
water, ammonia, sucrose, gold, o3ygen
%4
8/10/2019 Chap1 Chang
7/48
#compoundis a su(stance composed of atoms of two or
more elements chemically united in fi3ed proportions
Compounds can only (e separated into their pure
components 5elements6 (y chemical means 5e3ample:
decomposition,electrolysis6
Water (H2O) Glucose (C6H12O6)
Ammonia (H!)
%4
"ure su#stance- Homogeneous matter with a definite, or
fi3ed, composition
8/10/2019 Chap1 Chang
8/48
#n elementis a su(stance that cannot(e
separated into simpler su(stances (y chemical
means.
&%%2 elements ha*e (een identified
&7$ elements occur naturally on )arth
gold, aluminum, lead, o3ygen, car(on
&2% elements ha*e (een created (y scientists
technetium, americium, sea(orgium
%4
8/10/2019 Chap1 Chang
9/48
8/10/2019 Chap1 Chang
10/48
# mixtureis a com(ination of two or more su(stances
in which the su(stances retain their distinct identities
% Homogenous mixture8 composition of the
mi3ture is the same throughout
$ Heterogeneous mixture8 composition is not
uniform throughout
soft drin9, mil9, solder
cement,
iron filings in sand
%4
8/10/2019 Chap1 Chang
11/48
Mi$tures
Heterogeneous mixtures : has one or more visible
boundaries between the components.
Homogeneous mixtures :has no visible boundaries
because the components are mixed as individual atoms,
ions, and molecules.
Solutions : A homogeneous mixture is also called a solution.
Solutions in water are called aqueous solutions, and are very important in chemistry. Although we normally thin
o! solutions as li"uids, they can exist in all three physical
states.
8/10/2019 Chap1 Chang
12/48
Se%aratin& Mi$tures
Filtration : Separates components o! a mixture based upon
differences in particle size.#ormally separating a
precipitate !rom a solution, or particles !rom an
air stream.
rystalli!ation : Separation is based upon differences in
solubilityo! components in a mixture.
"istillation :separation is based upon differences in volatility.
Extraction :Separation is based upon differences insolubility in di!!erent solvents $ma%or material&.
hromatography : Separation is based upon differences
in solubility in a solvent versus a stationary phase.
8/10/2019 Chap1 Chang
13/48
Physical meanscan #e use' to se%arate a
mi$ture into its %ure com%onents
magnet
%4
distillation
8/10/2019 Chap1 Chang
14/48
i& 2*
iltration
8/10/2019 Chap1 Chang
15/48
Cr+stalli,ation
i& 2E
8/10/2019 Chap1 Chang
16/48
i& 2
8/10/2019 Chap1 Chang
17/48
i& 2G
8/10/2019 Chap1 Chang
18/48
"roce'ure -or Column C.romato&ra%.+
i& 2H
8/10/2019 Chap1 Chang
19/48
/0ESTIO 1
Classi-+ eac. o- t.e -ollo3in& as 4element5
4com%oun'5 4.omo&enous mi$ture5 or.etero&enous mi$ture
(a) Sil7er
(#) Et.+l alco.ol
Ans Element
Ans Com%oun'
(c) Ta#le salt Ans Com%oun'
(') C.ocolate c.i% coo8ies Ans Hetero&enousmi$ture
(e) Su&ar 'issol7e' in 3ater Ans Homo&enousmi$ture
8/10/2019 Chap1 Chang
20/48
%4
8/10/2019 Chap1 Chang
21/48
T.ree States o- Matter
%
solidli"uid
gas
8/10/2019 Chap1 Chang
22/48
T.e T.ree States o- Matter
8/10/2019 Chap1 Chang
23/48
".+sical C.an&e or C.emical C.an&e9
#physical changedoes not alter the composition or
identity of a su(stance
# chemical changealters the composition oridentity of the su(stance5s6 in*ol*ed
ice meltingsugar dissol*ing
in water
%;
hydrogen (urns in
air to form water
8/10/2019 Chap1 Chang
24/48
An extensive property o- a material 'e%en's
u%on .o3 muc. matteris is #ein& consi'ere'
An intensive property o- a material 'oes not
'e%en'u%on .o3 muc. matter is is #ein&
consi'ere'
&mass
&len&t.
&7olume
&'ensit+
&tem%erature
&color
E$tensi7e an' Intensi7e "ro%erties
%;
8/10/2019 Chap1 Chang
25/48
8/10/2019 Chap1 Chang
26/48
Matter - anything that occupies space and has mass
mass8 measure of the "uantity of matter
SI unit of mass is the kilogram59g6
% 9g < %=== g < % 3 %=2g
weight8 force that gra*ity e3erts on an o(>ect
weight < c3 mass
on earth, c< %=
on moon, c? =%
%@
# % 9g (ar will weigh
% 9g on earth
=% 9g on moon
8/10/2019 Chap1 Chang
27/48
%@
8/10/2019 Chap1 Chang
28/48
%@
8/10/2019 Chap1 Chang
29/48
Volume8 SI deri*ed unit for *olume is cu(ic meter 5m26
% cm2< 5% 3 %=-$m62< % 3 %=-;m2
% dm2< 5% 3 %=-%m62< % 3 %=-2m2
% A < %=== mA < %=== cm2< % dm2
% mA < % cm2
%@
8/10/2019 Chap1 Chang
30/48
Density8 SI deri*ed unit for density is 9gBm2
% gBcm2< % gBmA < %=== 9gBm2
density ects are consideredto ha*e an infinite num(er of significant figures
The a*erage of three measured lengths ;;4, ;;7 and ;@=.
;;4 F ;;7 F ;@=
2< ;;@222 < ;;@
Jecause 2 is an e3act num(er
< @
8/10/2019 Chap1 Chang
42/48
Accuracy8 how close a measurement is to the true*alue
Precision8 how close a set of measurements are to each other
accurate
K
precise
precise
(ut
notaccurate
notaccurate
K
notprecise
%7
*i i l A l i M t. ' ( t # l M t. ')
8/10/2019 Chap1 Chang
43/48
%
*imensional Anal+sis Met.o' (actor a#el Met.o')
o- Sol7in& "ro#lems
% etermine which unit con*ersion factor5s6 are needed
$ Carry units through calculation
2 If all units cancel e3cept for the desired unit5s6, then the
pro(lem was sol*ed correctly
% A < %=== mA
How many mA are in %;2 A.
%A
%=== mA%;2 A 3
< %;2= mA
%A
%=== mA
%;2 A 3 < ===%;2=A$
mA
8/10/2019 Chap1 Chang
44/48
T.e s%ee' o- soun' in air is a#out !=! mDs W.at
is t.is s%ee' in miles %er .our9
1 mile 16;< m 1 min 6; s 1 .our 6; min
!=!ms
$1 mile
16;< m
6; s
1 min
$6; min
1 .our
$ 6mile
.our
meters to milessecon's to .ours
%
/uestion 1
8/10/2019 Chap1 Chang
45/48
/uestion 1
Calculate the mass of $== ft2of lead, gi*en density
of lead is %%4 gBmA
5% ft < %$ inches % inch < $4 cm6
#nswer:
$== ft2 L%$ inches
% ft
2
L$4 cm
% inch
2
'olume