Lab 15 Chemical Physical Properties
Lab 15: Chemical and Physical Properties
Introduction
Pre-lab Questions
1. Determine if the following scenarios represent a chemical or physical property.
a. Dry ice (CO2) sublimes (changes from a solid to gas) at -78 ⁰C at standard atmospheric pressure.
Physical
b. Iron metal rusts in moist conditions.
Chemical
c. Hydrogen peroxide decomposes in the presences of light or heat.
Chemical
d. Silver metal does not react with hydrochloric acid (HCl).
Chemical
e. Copper is a reddish-brown color.
Physical
Lab 15: Chemical and Physical Properties
Experiment 1: Physical Properties of Water
Data
Table 1: Melting Point Data Initial Time
Final Time
Observations
Weigh Boat A 5:37 pm 7:00 pm
10 min- little puddle just started melting.
20 min- puddle under ice is a little bigger.
30 min- ice is melting more and getting a wetter appearance.
40 min- about half way melted.
50min- still slowly melting a bit more than half gone.
60 min- about a quarter of the cube remains.
70 min- a little les than a quarter remains.
83 min- cube completely melted.
Weigh Boat B 5:37 pm 6:34 pm
10 min- melting where the pile of salt is faster than A.
20 min- ice almost half way melted, especially where salt is.
30 min- most of the center of the cube is melted away.
40 min- almost all the way melted maybe a quarter of the cube left.
50 min- just about all gone small pieces remain.
57 min ice is completely melted.
Table 2: Freezing Point Data Initial Time
Final Time
Observations
Weigh Boat A 6:07 pm 7:37 pm 30 min- No change
60 min- partially frozen has ice crystals
90 min- frozen
Weigh Boat B 6:07 pm. 8:07 pm 30 min- No change
60 min- has very little ice forming
90 min- partially frozen still watery
120 min- mostly frozen
Post-lab Questions
1. Did both ice cubes melt at the same rate? Why or why not?
No the ice in tub B with the salt melted considerably faster.
2. Did both ice cubes re-freeze at the same time? Why or why not?
No the one in tub
Introduction
Pre-lab Questions
1. Determine if the following scenarios represent a chemical or physical property.
a. Dry ice (CO2) sublimes (changes from a solid to gas) at -78 ⁰C at standard atmospheric pressure.
Physical
b. Iron metal rusts in moist conditions.
Chemical
c. Hydrogen peroxide decomposes in the presences of light or heat.
Chemical
d. Silver metal does not react with hydrochloric acid (HCl).
Chemical
e. Copper is a reddish-brown color.
Physical
Lab 15: Chemical and Physical Properties
Experiment 1: Physical Properties of Water
Data
Table 1: Melting Point Data Initial Time
Final Time
Observations
Weigh Boat A 5:37 pm 7:00 pm
10 min- little puddle just started melting.
20 min- puddle under ice is a little bigger.
30 min- ice is melting more and getting a wetter appearance.
40 min- about half way melted.
50min- still slowly melting a bit more than half gone.
60 min- about a quarter of the cube remains.
70 min- a little les than a quarter remains.
83 min- cube completely melted.
Weigh Boat B 5:37 pm 6:34 pm
10 min- melting where the pile of salt is faster than A.
20 min- ice almost half way melted, especially where salt is.
30 min- most of the center of the cube is melted away.
40 min- almost all the way melted maybe a quarter of the cube left.
50 min- just about all gone small pieces remain.
57 min ice is completely melted.
Table 2: Freezing Point Data Initial Time
Final Time
Observations
Weigh Boat A 6:07 pm 7:37 pm 30 min- No change
60 min- partially frozen has ice crystals
90 min- frozen
Weigh Boat B 6:07 pm. 8:07 pm 30 min- No change
60 min- has very little ice forming
90 min- partially frozen still watery
120 min- mostly frozen
Post-lab Questions
1. Did both ice cubes melt at the same rate? Why or why not?
No the ice in tub B with the salt melted considerably faster.
2. Did both ice cubes re-freeze at the same time? Why or why not?
No the one in tub