Principle of Chemistry Laboratory (CHEM 1102 LAB)
Department of Chemistry
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CLASSES OF AND CHANGES IN MATTER
Abstract: Matter is complex, there are pure substances, which can be elements or compounds, and there
are mixtures, which can be heterogeneous or homogeneous. Familiarizing students about the differences of
substances is important because if these basic foundations of chemistry are not known, more complex
studies will be harder to grasp. After conducting many experiments, it is concluded that matter can be in
any form, but with observing and studying, its properties can be determined. Elements react with other
elements to form compounds, and compounds can react with other compounds or elements to form more
complex compounds, but their properties can be altered by subjecting them to chemical changes. Elements
and compounds can be combined physically to form mixtures, and separation processes can be executed to
reverse the combination.
Keywords: activation energy, decantate, decantation, dipole, dispersion forces, exothermic reaction,
orthorhombic property, polarization, precipitate, sublimation
sodium bicarbonate, is widely used for baking, and can be
used for treating heartburn, soothing canker sores, whitening
Introduction
Matter is full of complexities. There are pure
teeth, relieving itchy skin and sunburns, among others
substances; there are mixtures. Pure substances can be
(Raman, 2017). Moving on, iron pellets are small balls of iron
elements or compounds. These substances have no
ore that are used for the production of steel used in the
components of other substances (Omondi, 2017). Elements
construction of bridges, planes, household appliances, and
are substances that contain only one kind of atom, while
more (Vale, 2017). Iron chloride (FeCl3) can also be called
compounds are substances that contain two or more kinds of
ferric chloride, which is a highly corrosive and acidic
atoms combined chemically with definite proportions.
compound used for sewage treatment and water purification
Mixtures, on the other hand, are combinations of two or more
(“Ferric Chloride”, n.d.). Magnesium ribbons are light,
pure substances combined physically. Mixtures can be
silvery-white, and moderately hard metallic form of
homogeneous or heterogeneous. Homogeneous mixtures
magnesium that burns with a brilliant white flame (The Free
have substances combined in a uniform composition, while
Dictionary, n.d.), while table salt a white crystalline solid that
heterogeneous mixtures have substances that doesn’t mix
is one of the many abundant minerals on earth (“Sodium
evenly, thus containing visibly different substances or phases
Chloride,” n.d.). Hydrochloric acid is a highly corrosive acid
(Virtual ChemBook, 2003).
used industrially to process steel and in the production of
Matter is everywhere, and there are always conditions
batteries, photoflash bulbs, and fireworks (American
that make matter subject to change. Changes in matter can be
Chemistry Council, 2003), while sodium hydroxide (NaOH)
physical or chemical. Chemical changes produce new
or lye is commonly used as a drain cleaner in its concentrated
substances, while physical changes do not. Chemical change
form (National Research Council, 1984), and hydrogen
is a result of a chemical reaction, while physical change is
peroxide (H2O2) is a colorless liquid used primarily for
when a matter changes its form but not its chemical identity
bleaching, as a rocket propellant, and for cosmetic and
(Helmenstine, 2019).
medicinal purposes (The Editors of Encyclopaedia
The goal of this experiment is for the students to know
Britannica, 2018).
the differences between substances and mixtures and learn
Distilled water (H2O), sand, 2x2in sandpaper (Grit
how to differentiate between the two, and for them to be able
size: 220), and table sugar (C12H22O11) are also used,
to list the distinction between physical and chemical changes.
provided by the experimenters.
Materials and Methods
1. Samples and Reagents
Sulfur, moth ball, baking soda (NaHCO3), iron pellets,
iron(III) chloride (FeCl3), Magnesium (Mg) ribbon, table salt
(NaCl), diluted hydrochloric acid (HCl), sodium hydroxide
(NaOH), and hydrogen peroxide (H2O2) are the reagents used
for the experiment, all of which are provided by the
laboratory. Sulfur is a nonmetallic element and is one of the
most reactive of the elements (Brasted, 2019). Moth balls are
small round discs of chemical pesticides, usually made of
naphthalene or para-dichlorobenzene (Cleanipedia, 2019).
On the other hand, baking soda (NaHCO3), also called
2. Classes of Matter
For this experiment, sulfur, magnesium ribbon, moth
ball, table salt, and sand were used with a goal of learning
about pure substances and mixtures and some ways on how
they can be separated.
2.1. Elements and Compounds
0.5 g of sulfur was observed for its color, odor and
physical state. The sulfur was then subjected to heat and was
compared to the its unheated form. After the sulfur
experiment, Mg ribbon was cleaned with a sandpaper, its
physical properties are observed. The Mg ribbon was ignited
and was also compared to its unignited form.
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2.2. Mixtures
Moth balls are grinded to powder using a mortar and
pestle. 0.25g of moth ball powder was mixed evenly to 0.5g
of table salt. The result was observed. 0.5g of sand was mixed
to the solution and the mixture was also observed.
2.3. Separation of the Components of a Mixture
The mixture of moth ball powder, salt, and sand was
transferred to a beaker where 30mL of water was added and
mixed. The solution underwent decantation to separate the
solid particles that settled at the bottom of the beaker. The
decantate was transferred to an evaporating dish and was
covered with an inverted funnel, then underwent heating for
evaporation to separate the particles mixed together.
3. Physical and Chemical Change
Table salt, table sugar, iodine crystal, HCl solution,
and NaHCO3 were the chemicals used for the experiment.
Learning the physical and chemical changes of matter was
the objective for conducting this experiment.
3.1. Salt and Sugar
0.5g of salt was dissolved in 2mL of distilled water.
The solution was transferred to an evaporating dish and the
solvent was evaporated. This process was repeated with 0.5g
of table sugar and the residues of the salt solution and sugar
solution were observed.
3.2. Iodine Crystal
1 to 2 crystals of iodine were placed in an evaporating
dish, covered with an inverted funnel, and subjected to heat.
After cooling, the residue on the sides of the funnel were
observed.
3.3. Sodium Bicarbonate (NaHCO3)
2mL of HCl solution was placed in a test tube. A small
amount of NaHCO3 was added and the reaction of the two
substances were observed.
4. Types of Chemical Change
The reagents used for this experiment are a
magnesium ribbon, 2mL of H 2O2, 2mL of HCl, iron fillings,
an mL of NaOH, and an mL of FeCl3. This experiment was
conducted to learn the different types of chemical changes
and reactions when chemicals are subjected to some
conditions and with each other.
4.1. Synthesis
A piece of Mg ribbon was held with a crucible tong
and was ignited. The results were observed.
4.2. Decomposition
2mL of H2O2 was placed in a clean test tube and
observed for a minute.
4.3. Displacement or Substitution
2mL of HCl solution was placed in a test tube. A
granule of iron was dropped in the solution. The reaction of
the two chemicals were observed.
4.4. Double displacement or Metathesis
An mL of NaOH was placed in a test tube, then an mL
of FeCl3 was added to the tube. The reaction of the two
chemicals were observed.
5. Waste Management
All wastes generated from this experiment must be
placed at the Inorganic waste container.
Results and Discussion
1. Classes of Matter
Table 1.1. Elements and Compounds
Sulfur
Properties
Unheated
Color
Yellow
Odor
Odorless
Physical
state
Crystalline
or
Powdered
like (solid)
Heated
Red
orange
to dark
brown
Roasting
odor
Liquid
Mg ribbon
UnIgnited
ignited
Grayish
(metal
color)
White
Odorless
Odorless
Solid
Ash like
structure
The table shows the data that has been acquired
through the experiment. Sulfur turns red orange to black
when too much exposure to heat is applied. It also turns into
its plastic form with the absence of heat. For Mg ribbon, it
gives vivid light and produce ash like or powdered structure.
Elements are composed of only one kind of atom
while compounds are composed of two or more elements
(Eugenio, n.d.). In the experiment, sulfur is exposed to heat
and, from its yellow color, turned to a red orange to dark
brown, wherein in further heating will turn it into black.
Meanwhile, sulfur will turn into its plastic form when cooled
down (“Melting Sulfur”, 2015). This is because of the
orthorhombic property of sulfur powder. In crystallography,
the orthorhombic crystal system is one of the 7 crystal
systems (The Editors of Encyclopaedia Britannica, 2017).
When igniting Mg ribbon, it projects white bright light and
becomes ash like and white in color. Both sulfur and
magnesium, when ignited, reacts with the oxygen in the air,
forming sulfur dioxide and magnesium oxide, respectively.
Principle of Chemistry Laboratory (CHEM 1102 LAB)
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Figure 1.1. Sulfur
Figure 1.2. Sulfur when
heated
Table 1.2. Mixture of moth ball, salt, and sand
Mixture
Description
Type of Mixture
White in color,
the mothball and
Mothball +
Homogeneous
salt cannot be
Salt
mixture
distinguished
anymore
Dirty white in
color, the sand is
Mothball +
Heterogeneous
visible compared
Salt + Sand
mixture
to the mothball
and salt
This table presents the results of the mixture of
mothball and table salt, along with the addition of sand. For
the mixture of mothball and sand, once the mixture was
uniform as possible, the mixture remains white in color.
Aside from that, the grinded mothball and the table salt
cannot be distinguished anymore. This mixture is
homogenous. On the other hand, the combination of grinded
mothball, salt, and sand resulted in a dirty white color, due to
the color of sand dominating the other two. In contrast with
the first mixture, wherein the mothball and salt cannot be
discerned from each other anymore, the sand can be clearly
seen despite being distributed in the mixture. The addition of
sand made the mixture heterogenous.
Table 1.3. Separation of the Components of a Mixture
Component
The mixture after mixing
with water
Decantate
Residue on the side of funnel
Residue on the bottom of the
evaporating dish
Description
The salt dissolved, the
mothball powder floated, and
the sand sank to the bottom
of the container.
It was a transparent white
that has solid mothball
powder floating on it.
Crystals formed on the sides
of the funnel. It was white,
sparkly, and smells pungent.
Salt was formed and left on
the dish after evaporating the
water.
The mixture from the preceding experiment was
separated to its components. After adding water to the
mixture, the salt dissolved in the water, the grinded mothball
floated, while the sand sank to the bottom of the container.
Despite stirring, the sand still settles to the bottom while the
mothball powder still floats on top. The mixture was
transferred to another beaker to separate the sand particles.
This process of separating the precipitate, or the solid
components, from the liquid layer is called decantation
(Helmenstine, 2019). The decantate contains the salt solution
and mothball powder. It was a transparent liquid that has
mothball powder floating on top. Next, the decantate was
heated to separate the mothball powder from the mixture in a
process called sublimation, which is the direct transition from
solid state to gas state. Because of the heat, the mothball
sublimed, leaving small crystals on the side of the funnel. The
crystals were white and sparkly, which still smells pungent
like its solid form. Left with the salt solution, the solution was
heated continuously until the water evaporated. Water
particles keep the salt particles from going back to salt
crystal, therefore, lack of water results in salt recrystallizing
which leaves a solid salt (“Evaporation”, n.d.). Through
decantation, sublimation, and evaporation, the components of
the mixture are then separated.
Figure 1.3.
Sand gathered
after decantation
Figure 1.4.
Decantate
2. Physical and Chemical Change
Table 2.1. Salt and Sugar
Substance Type of Change
Figure 1.5.
Mothball
crystals
Justification
Salt solution, when
heated, will allow the
water to evaporate
Table salt Physical change
while the salt returned
to its solid
crystallized form.
Water in sugar
solution evaporated;
sugar also broke
Table
Chemical change down and was
sugar
caramelized into a
dense, brown
substance.
In this experiment 0.5g of salt were weighted and
dissolved in a 2mL distilled water. The solution was then
exposed to heat until the liquid evaporated. The process was
repeated with sugar. When the salt solution underwent
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evaporation, the water became gas while salt goes back to its
original state. Because salt has a high melting point, it turned
back to solid form as water evaporated. In the sugar solution,
the sugar caramelized after water evaporated. This is because
sugar is made up of carbon, hydrogen and oxygen atoms.
When heated over an alcohol lamp, these elements react with
the fire to turn into liquid. Physical change is present in salt
because it remained unchanged while chemical change is
present in sugar. Physical change is a type of change in which
the form of matter is altered but one substance is not
transformed into another. The size or shape of matter may be
changed, but no chemical reaction occurs (Helmenstine,
2019), which happens in the salt solution. Meanwhile,
chemical change is a process where one or more substances
are altered into one or more new and different substances. In
other words, a chemical change is a chemical reaction
involving the rearrangement of atoms (Helmenstine, 2019),
which happens in the sugar solution.
Table 2.2. Heating of Iodine Crystal
Substance Type of Change
Justification
The iodine Crystals
(solid) changes into a
purple- colored
vapour (gas) with a
harsh odor when
Iodine
heated. This process
Physical Change
Crystal
(solid transition to
gas without passing
through liquid state)
is called sublimation
which is a type of
physical change.
This table shows the type of change the iodine crystals
underwent when it was subjected to heat.
Crystals of iodine are obviously solid-phased. When it
was heated, the solid crystals change its phase to a purplecolored vapor. The transition of the solid phased iodine
crystal to a gaseous state purple vapor is a process of
sublimation. When the iodine crystals are heated, it sublimes.
This is because the attractive force present in iodine
molecules called Van der Waals dispersion forces is
relatively weak due to the absence of a permanent dipole in
iodine (Khan, 2018). Van der Waals dispersion forces is the
weakest among the intermolecular forces. It is caused by
polarization and results to formation of temporary dipoles,
making one side temporary negative and the other temporary
positive (Apodaca, 2017). Owing to the fragility of the
mentioned intermolecular force, iodine in solid state
succumbs easily when heated and changes into gas state. This
process is identified as a physical change because solid iodine
can be regained from vapor state by cooling which makes the
process a reversible reaction. In the experiment, it is evident
that the vapor formed a solid crystal on the surface of the
inverted funnel when it was cooled.
Figure 2.1. Iodine crystals on the side of the funnel.
2.3. Sodium Bicarbonate in HCl solution
Substance Type of Change
Justification
When a pinch of
NaHCO3 was added,
the color of the HCl
NaHCO3
Chemical change solution changed,
with salt, water, and
carbon dioxide as a
product.
When a pinch of NaHCO3 was added, the color of the
2mL HCl solution changed forming a light pink mixture
because of the chemical reaction, therefore undergoing
chemical change.
When sodium bicarbonate and hydrochloric acid mix,
two molecules of HCl give their hydrogen atoms to the
sodium carbonate. This produces carbonic acid, with the
formula H2CO3. The sodium from sodium carbonate forms a
salt with the chloride particles from HCl, producing sodium
chloride (NaCl). Carbonic acid is quite unstable. The reaction
produces small quantities of carbon dioxide gas, water, and
table salt.
NaHCO3 + HCl
NaCl + H2O + CO2
Figure 2.2. Reaction of NaHCO3 + HCl
3. Types of Chemical Change
Table 3.1. Ignition of Mg ribbon
Type of
Chemical
Observation
Chemical Product
Change
When the Mg
ribbon was ignited,
Synthesis
it burned and
Magnesium oxide
produced white
fire.
As the Mg ribbon ignited, it burned quickly and
produced a white fire. After the whole ribbon was burned, it
formed a sort of white powderish residue.
When magnesium is in its metal form it will burn very
easily in air. However, in order to start the reaction (the
burning) the magnesium metal needs a source of energy. The
flame provides a source of heat so that the magnesium metal
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atoms can overcome their activation energy. Activation
energy is the minimum energy required in order for a
chemical reaction to proceed (Khan Academy, 2019). When
the magnesium metal burns, it reacts with oxygen found in
the air to form Magnesium Oxide. Oxygen and magnesium
combine in a chemical reaction to form this compound. After
it burns, it forms a white powder of the magnesium oxide.
Magnesium gives up two electrons to oxygen atoms to form
this powdery product. This is an exothermic reaction. An
exothermic reaction is a term that describes a chemical
reaction in which there is a net release of energy (heat) (Khan
Academy, 2019).
2Mg + O2
2MgO
Figure 3.1. Synthesis reaction of magnesium and oxygen
Table 3.2. Decomposition of hydrogen peroxide (H2O2)
Type of
Chemical
Chemical
Observation
Product
Change
Hydrogen Peroxide
(H2O2) when
transferred into the
test tube is a
colorless liquid.
After a few minutes Water
of observation, it
and
Decomposition
slowly forms
Oxygen
bubbles of oxygen
gas
gas. Its exposure to
light and air causes
it to be broken into
water and oxygen
gas.
This table shows the observation result of the
decomposition of hydrogen peroxide into water and oxygen
gas.
Hydrogen Peroxide (H2O2) is a colorless liquid widely
used as a disinfectant and a bleaching agent. It is usually
stored in light-blocking brown bottles as the reagent is
sensitive to light and temperature (National Center for
Biotechnology Information, 2019). In the experiment,
Hydrogen Peroxide was transferred to a test tube for
observation. After a few minutes, the compound catalyzed a
reaction which causes the compound to form bubbles. This is
because Hydrogen Peroxide actually underwent a
decomposition reaction due to its exposure to light and higher
temperature. A decomposition reaction is defined as a type of
chemical reaction in which one reactant yields two or more
products (Helmenstine, 2019). In the case of Hydrogen
Peroxide, it was broken down into water (H20) and oxygen
gas (O2). This explains that the bubbles formed are actually
bubbles of oxygen gas.
2H2O2
2H2O + O2
Figure 3.2. Decomposition reaction of hydrogen peroxide
Figure 3.3. Water and oxygen (in bubbles) after
decomposition of hydrogen peroxide
Table 3.3. Iron Pellets in HCl Solution
Type of
Chemical
Chemical
Observation
Product
Change
Tiny bubbles
Iron(II) chloride
appeared when the
Displacement
and hydrogen
iron pellet was put
gas
in the solution.
Tiny bubbles appeared after a while when the granule
of iron settled at the bottom of the HCl solution.
When solid iron filings are added to dilute aqueous
hydrochloric acid, Iron(II) chloride or ferrous chloride is
formed, with the liberation of hydrogen gas. Hydrochloric
acid, however, can dissolve iron, and a more concentrated
solution will dissolve it more rapidly.
Fe + 2HCl
FeCl2 + H2
Figure 3.4. Substitution reaction
Table 3.4. Chemical reaction of NaOH and FeCl3
Type of
Chemical
Chemical
Observation
Product
Change
Upon mixing NaOH
and FeCl3, a dark
brown precipitate was
formed. This is
Fe(OH)3 +
Metathesis Fe(OH)3, the product
3NaCl
of the reaction along
with NaCl, which
dissolved in the
liquid.
This table explains the reaction that happened after
mixing NaOH (sodium hydroxide) and FeCl3 (ferric
chloride). Double displacement reaction, or metathesis
reaction, is a type of chemical reaction where the cations and
anions of two reactants switch places, forming two new
products in the process (Garcia, n.d.). It has a general formula
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of AB + CD = CB + AD. During the reaction, the cations
sodium and iron switch places, forming sodium chloride and
ferric oxyhydroxide. The result was a dark brown precipitate,
which is actually the ferric oxyhydroxide. Ferric
oxyhydroxide does not dissolve in water, that’s why it
became a precipitate of the solution. Another product was
formed, which is table salt, but was not visible because it
dissolved in the liquid. If the solution was filtered out, the
residue will be the ferric oxyhydroxide while the filtrate will
be the sodium chloride solution.
FeCl3 + 3NaOH
Fe(OH)3 + 3NaCl
Brasted, R. (2019, January 10). Sulfur. Retrieved from
https://www.britannica.com/science/sulfur
Cleanipedia. (2019, June 21). What Are Moth Balls & How
Do
You
Use
Them?
Retrieved
from
https://www.cleanipedia.com/ph/in-thehome/moth-balls-use.html
Eugenio, P. (n.d.) Class and Changes in Matter [PowerPoint
presentation]. Nueva Ecija, Philippines.
Ferric
Figure 3.5. Metathesis reaction of NaOH and FeCl3
Chloride.
(n.d.)
Retrieved
from
https://thechemco.com/chemical/ferric-chloride/
Helmenstine, A. (2019, January 12). Decomposition
Reaction
Definition.
Retrieved
from
https://www.thoughtco.com/definition-ofdecomposition-reaction-604995
Helmenstine, A. (2019, May 10). Examples of Physical
Changes and Chemical Changes. Retrieved from
https://www.thoughtco.com/physical-andchemical-changes-examples-608338
Figure 3.6.
Mixing FeCl3 and NaOH
Figure 3.7.
Precipitate formed
Conclusions
Conclusions were made after conducting all the
experiments. Elements are always subject to changes because
of many conditions in the surroundings, proved by sulfur and
magnesium reacting with oxygen upon being ignited to form
a compound, combined chemically. Mixtures can be made by
physically mixing elements or compounds and can be
homogeneous or heterogeneous in nature. There are different
ways to separate mixtures, decantation and evaporation are
an example. Changes in matter can be physical, where the
form or phase of matter changes but not its chemical
composition, or chemical, where a substance's composition is
altered to form a new and different substance. lastly, there are
different types of chemical changes, synthesis reaction,
decomposition reaction, displacement reaction, and
metathesis reaction, among others.
References
American Chemistry Council. (2003, November).
Hydrochloric Acid-HCl-An Acid with Many Uses.
Retrieved
from
https://chlorine.americanchemistry.com/ScienceCenter/Chlorine-Compound-of-the-MonthLibrary/Hydrochloric-Acid-HCl-An-Acid-WithMany-Uses/
Apodaca, D. (2017). General Chemistry 2. Makati,
Philippines: Diwa Learning Systems Inc.
Helmenstine, A. (2019, May 23). What Are Physical Changes
in
Chemistry?
Retrieved
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https://www.thoughtco.com/definition-of-physicalchange-605910
Helmenstine, A. (2019, May 10). What a Chemical Change
Is and How to Recognize It. Retrieved from
https://www.thoughtco.com/definition-ofchemical-change-604902
Khan, F. (2018). What Type of Intermolecular Forces are
Between Iodine Molecules? Retrieved from
https://www.quora.com/What-type-ofintermolecular-forces-are-between-iodinemolecules
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https://www.khanacademy.org/science/highschool-biology/hs-energy-and-transport/hsenzymes/a/activation-energy
Khan Academy. (2019). Endothermic vs. Exothermic
Reactions.
Retrieved
from
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Melting
Sulfur.
(2015).
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from
https://melscience.com/US-en/experiments/sulfurmelt/
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National Center for Biotechnology Information. (2019).
Hydrogen
peroxide.
Retrieved
from
https://pubchem.ncbi.nlm.nih.gov/compound/Hydr
ogen-peroxide
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Retrieved
from
https://www.worldatlas.com/articles/what-is-apure-substance.html
Raman, R. (2017, November 24). 23 Benefits and Uses for
Baking
Soda.
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from
https://www.healthline.com/nutrition/baking-sodabenefits-uses
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Chloride.
(n.d.).
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https://www.britannica.com/science/hydrogenperoxide
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8). Orthorhombic System. Retrieved from
https://www.britannica.com/science/orthorhombicsystem
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Solutions?
Retrieved
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http://chemistry.elmhurst.edu/vchembook/106Ami
xture.html
Questions
1. Give 3 other examples of homogeneous and heterogeneous
mixture.
Other examples of homogeneous mixtures are steel, blood
plasma, and dishwashing liquid. Blood, beach sand, and
clouds, on the other hand, are heterogeneous mixtures.
2. Give some differences between chemical and physical
changes
Chemical changes happen when there is a change in the
properties of molecules. When one substance became
another, that is a chemical change. Meanwhile, physical
changes can disrupt the appearance of a substance but
chemically, nothing changed on it. Physical changes can be
undone when energy is put into it, but in chemical changes,
the only way to reverse it is through another chemical
reaction.
3. Classify the following changes
a. Rusting of iron
b. Yellowing of leaves
c. Milling of rice
d. Roasting of meat
e. Water cycle
f. Washing of dishes
g. Burning of wood
h. Melting of candle
i. Drying of clothes
j. Decoration of stain with bleach
chemical change
chemical change
physical change
chemical change
physical change
physical change
chemical change
physical change
physical change
chemical change