EXPERIMENT REPORTMASS OF SUBSTANCES IN CHEMICAL REACTION
GROUP V :
PUTRI MEGA ANANDA (123 194 205 )
ZAIMATUL UMAH (123 194 232)
RADIAN DANY APRILIA (123 194 236)
THE STATE UNIVERSITY OF SURABAYAFACULTY OF MATHEMATICS AND NATURAL SCIENCES
DEPARTMENT OF CHEMISTRY 2012
A. TITTLE : MASS OF SUBSTANCES IN CHEMICAL
REACTION
B. DATE OF EXPERIMENT : October, 16th 2012
C. PURPOSE : Learning about Law of Mass Conservation
D. THEORY :
The law of conservation of mass, also known as the Lomonosov-Lavoisier
law. Lomonosov-Lavoisier law is a law that states the mass of a closed system is
constant despite the wide range of processes in the system (in a closed system mass of
substances before and after the reaction is the same (fixed / constant)) . Statements
that are commonly used to express the law of conservation of mass is the mass can
change form but can not be created or destroyed. For a chemical process in a closed
system, the mass of the reactants must equal the mass of the product.
The law of conservation of mass is widely used in fields such as chemistry, chemical
engineering, mechanics, and fluid dynamics. Based on the science of special
relativity, conservation of mass is a statement of conservation of energy. The mass of
the particles that remain in a system equivalent to the energy momentum of its center.
In some instances the radiation, it is said that the apparent mass change into energy.
This occurs when an object is transformed into kinetic energy / potential energy and
vice versa. Since mass and energy related, in a system that gets / expend energy, the
mass in very small amounts will be created / missing from the system. However, in
almost all events that involve changes in energy, law of conservation of mass can be
used as mass changed very little.
Example of the law of conservation of mass
The law of conservation of mass can be seen in the reaction to the formation of
hydrogen and oxygen from water. When hydrogen and oxygen formed from 36 g of
water, then when the reaction takes place until all the water runs out, the masses will
be obtained product mixture of hydrogen and oxygen is 36 g. When the reaction still
leaves the water, the mass of a mixture of hydrogen, oxygen and water unreacted
fixed at 36 g.
History of Law of Conservation of Mass
Law of conservation of mass, formulated by Antoine Lavoisier in 1789. Because of
this result, it is often referred to as the father of modern chemistry. Earlier, Mikhail
Lomonosov (1748) also has proposed a similar idea and has been proven in
experiments. Previously, the conservation of mass, difficult to understand due to the
force of Earth's atmosphere buoyan. Once the style is understandable, the law of
conservation of mass to be of key importance in changing alchemy into modern
chemistry. When scientists understand that the compound has never lost when
measured, they began to study the quantitative transformation of compounds. This
study led to the idea that all the chemical processes and transformations take place in
a fixed amount of mass of each element.
The law of conservation states that a particular measurable property of an isolated
physical system does not change as the system changes. Here is a list of some of the
laws of conservation that never show inappropriate. (Actually, in general relativity,
energy, momentum, and angular momentum is not conserved because no general
curve time space "manifold" which does not have a murder to translational symmetry
or rotation).
Chemicals associated with the interaction of matter that could involve two substances
or between matter and energy, especially in relation to the first law of
thermodynamics. Traditional chemistry involves interactions between chemicals in a
chemical reaction, a change of one or more substances into one or more other
substances. Sometimes the reaction is driven by enthalpy considerations, such as
when two substances such high enthalpy elemental hydrogen and oxygen react to
form water, a substance with a lower enthalpy. Chemical reactions can be facilitated
with a catalyst, which is generally an other chemicals involved in the reaction media
but not consumed (eg : sulfuric acid which catalyzes the electrolysis of water) or
immaterial phenomena (such as electromagnetic radiation in photochemical
reactions). Also deal with traditional chemical analysis of chemical substances, both
inside and outside of a reaction, as in spectroscopy.
D. DESIGN OF EXPERIMENT
1. PICTURE SERIES OF EXPERIMENT
2. EQUIPMENT AND MATERIALS :
Equipment :
Erlenmeyer = 1 piece
Rubber cork = 1 piece
Small test tube = 1 piece
Yarn = ± 40cm
Balance = 1piece
Materials :
CuSO4 0,2 M = 5 ml
NaOH 0,2 M = 10 ml
Pb(NO3)2 0,2 M = 5 ml
KI 0,2 M = 10 ml
3. Experiment Steps
1. Pouring 10 ml of NaOH 0,2 M into Erlenmeyer, beside that pouring 5ml of
CuSO4 0,2 M into small test tube. Putting filled small test tube into the
Erlenmeyer (test tube hanged by yarn) then covered it with cork.
2. Balancing Erlenmeyer and its fill, then writing down the mass.
3. Canting small test tube so that both of substances are mixed. Observing what happened after that.
4. Balancing Erlenmeyer and its fill, then writing down the mass (after reaction).
5. Pouring 10 ml of KI 0,2 M into Erlenmeyer, beside that pouring 5ml of
Pb(NO3)2 0,2 M into small test tube. Putting filled small test tube into the
Erlenmeyer (test tube hanged by yarn) then covered it with cork.
6. Balancing Erlenmeyer and its fill, then writing down the mass.
7. Canting small test tube so that both of substances are mixed. Observing what happened after that.
8. Balancing Erlenmeyer and its fill, then writing down the mass (after reaction).
E. PROCEDURE
Entered to Reaction tube
Entered to Erlenmeyer tube Bonded with yarn entered to Erlenmeyer and closed the
mouth with rubber cork
Measure with ohausee balance
Write the mass
Sloping the reaction tube, so both of the solution can mix
Measure again with ohausee balance
Mass Before Reaction same after Reaction
Erlenmeyer Flask
Mass Before Reaction
Reaction Tube
Erlenmeyer Flask
10 ml NaOH 0.2 M
Reaction Tube
5 ml CuSO4 0.2 M
Mass Before Reaction same after Reaction
Erlenmeyer Flask
Mass Before Reaction
Reaction Tube
Erlenmeyer Flask
10 ml KI 0.2 M
Reaction Tube
5 ml Pb(NO3)2 0.2 M
F. RESULT OF EXPERIMENT
No Prosedure Result Reaction Conclution
1
1.2.3.
- The mass of
substance before
and after the
reaction are same.
- Mass before
reaction is 154.4
grams and mass
after reaction is
154.4 grams.
- In the reaction
produce sedimen,
and the colour is
young blue.
-The changed of
color are occur.
-The colour of
sedimen : dark blue.
- The color of
NaOH : no colour,
CuSO4 : : young
blue
- 2NaOHaq) +
Cuso4(aq)
(reactan)
- 2NaOHaq) +Cuso4(aq)
➝Na2SO4(aq)+
Cu(OH)2 (s)
-Mass can
change if
rubber cork
opened
-Mass nothing
will change
despite
denature of the
exchange
between the
substance of
the system.
- the
conservation
law of mass
proved with
result of mass
before reaction
same with
mass after
reaction.
Mass Before Reaction same after Reaction
Erlenmeyer Flask
Mass Before Reaction
Reaction Tube
Erlenmeyer Flask
10 ml NaOH 0.2 M
Reaction Tube
5 ml CuSO4 0.2 M
Mass Before Reaction same after Reaction
Erlenmeyer Flask
Mass Before Reaction
Reaction Tube
Erlenmeyer Flask
10 ml KI 0.2 M
Reaction Tube
5 ml Pb(NO3)2 0.2 M
Na2SO4(aq)
+ Cu(OH)2 (s)
(reaction)
-2KI(aq)+Pb(NO3)2(aq)
(reactan)
-2KNO3(aq) +PbI2(s)
(product)
-Mass before
reaction is 155,8
grams and mass of
the reaction 155,8
grams
- There is occur
sediment in that
reaction and the
sediment and
reaction color is
yellow.
-There is no color in
KI reaction
-Pb(NO3)2 have not
color.
- the mass of
substance before
and after reaction is
the same.
➝2KNO3(aq) +PbI2(s)
2KI(aq)+Pb(NO3)2(aq)
F. ANALYSIS
To know about the mass of substance in chemical reaction, first we take 5 ml of CuSO4 0,2 M in test tube while take 10 ml of NaOH 0,2 M in Erlenmeyer. Then put test tube in Erlenmeyer (test tube hanged by yarn) then covered Erlenmeyer with cork. And then we balance Erlenmeyer and its fill, then writing down the mass of it. From the balance, we get the data that mass of it before reaction is 154,4grams. After that, we react both of substance. Repeat to balance the mass after reaction and we get the data that mass is the same with before, 154,4 grams. The chemical reaction is
CuSO4(aq)+2NaOH(aq) → Na2SO4(aq) + Cu(OH)2(s)
For second experiment, we do it in the same way with first experiment. But, we change CuSO4 with 5ml of Pb(NO3)2 0,2M and NaOH changed with 10 ml of KI 0,2M. From the experiment we get data that mass before reaction is 155,8 grams. And after reaction the mass is same, 155, 8 grams. The chemical reaction is
2KI(aq)+Pb(NO3)2(s)→ 2KNO3(aq) + PbI2(s)
G. DISCUSSION
To proof the Law of Conservation of Mass we do two experiments. First experiment, we use CuSO4 react with NaOH. And the second experiment we react Pb(NO3)2 with KI. From both of the result we know that there are nothing change with the mass in chemical reaction (mass before reaction and mass after reaction). It is because we covered the Erlenmeyer with cork, so the gasses that maybe produce can not came out. In our experiment there is an accident because we spent lot of time to balancing the balance, so that the color of our second experiment change become dark green with sediment, but the change of color dosn’t make effect to the mass of reactions
H. CONCLUSIONMass can change if rubber cork opened. Mass nothing will change despite
denature of the exchange between the substance of the system. The conservation law
of mass proved with result of mass before reaction same with mass after reaction.
I. ANSWER OF QUESTION
1 Law is a readily observable fact about something. It is something that is obvious and undeniable.
Theory is an advanced hypothesis. An hypothesis is a plausible, testable explanation of how a phenomenon works and why it works that way.
2 Theory Dalton said that the matter consist of atom that can’t divided. Every substance consist of atom with identical characteristic and mass, and the substance formed if the atom of some element and collect in constant composition.
And the law of conversion mass said mass before and after reaction is same.
So it caused atom can’t be divided and has identical characteristic and mass so mass before and after reaction is same.
3 When magnesium was burned, appear the reaction 2Mg + O2 → 2MgO
so, the mass of MgO is bigger than Mg, because there is mass increase of O2 to Mg
4 Experiment 1: CuSO4(aq)+2NaOH(aq) → Na2SO4(aq) + Cu(OH)2(s)
Experiment 2: 2KI(aq)+Pb(NO3)2(s)→ 2KNO3(aq) + PbI2(s)
REFERENCE
en.wikipedia.org/wiki/chemical_reaction, 17 October 2012 at 18:59.
ariphudien.blogspot.com/2011/02/blog-post.html, Selasa, 15 Februari 2011
Tim Kima Dasar;(2010),Kimia Dasar 1, UNESA, Surabaya.
ATTACHMENT
No Explanation Photo
1. First setting of equipment
2. First experiment, materials of AgCO3 and NaOH
3. Placed AgCO3 and NaOH on the tube
5. Result that produce after mixture AgCO3 and NaOH
5. The substance become green with
sediment because to long waiting for
the measurement.
6. Second setting of equipment
7. Second experiment, materials ofKI and Pb(NO3)2
8. Result that produce after mixture KI and Pb(NO3)2