105a postlab1
.docx
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University of Southern California *
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Course
105
Subject
Chemistry
Date
Jan 9, 2024
Type
docx
Pages
5
Uploaded by ColonelEnergySeaUrchin26 on coursehero.com
Data
Trial 1: pipet
density
=
sample
+
beaker
−
beaker
volume
Density for 2% NaCl:
85.4
−
80.2
5.2
=
1
g
/
cm
3
Average density for water:
1.234
+
0.8
+
0.966
+
1.126
4
=
1.0315
Standard deviation for DI density:
√
(
1.234
−
1.0315
)
2
+(
0.8
−
1.0315
)
2
+(
0.966
−
1.0315
)
2
+(
1.126
−
1.0315
)
2
4
=
0.1895776
%error(accuracy) for water=
¿
averagevalue
−
truevalue
∨
¿
truevalue
¿
×100%
=
1.0315
−
1
1
×100%=3.15%
Trial2: buret
Average DI water density: 0.9955g/cm3
Standard deviation for water density: 0.0198
%error(accuracy) for water=
¿
averagevalue
−
truevalue
∨
¿
truevalue
¿
×100%
=
1
−
0.9955
1
×100%=0.45%
Percent error in buret trial is smaller, so buret is more accurate than pipet.
Graph
Trial 1
Linest equation
y = -0.0006x + 1.0665
Unknown B density: 1.01923g/cm3
x=
1.01923
−
1.0665
−
0.0006
=
¿
78g/cm3 (invalid data)
buret Trial 2
LINESTequation
Unknown B density: 1.01923g/cm3
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