Nat Sci Reviewer

8/3/2019 Nat Sci Reviewer

1/10 Physical Science

NAT SCI REVIEWER

Lesson 1.1 Science and its History

Science is an established data gathered to uncover

general truths resulting from a study.

It comes from the Latin word:

Sciere (which means to know) and Scientia

(which means knowledge)

Pure Science is concerned with the gathering

information solely for the sake of obtaining new

knowledge.

Applied Science it is also called Technology, Is a

practical application of scientific theoryand law that

can be used in everyday situation.

TWO MAiN DiViSiON OF SCiENCE:

y Physical Sciencey Biological ScienceBiology Study of life

Botany Study of Plants

Zoology Study of Animals

Physical Science is the science that deals with

nature, behavior and relationship between matter

and energy in non-living things.

BRANCHES OF PHYSICAL SCIENCE

y Physics deals with the changes in matterand energy, their interaction which do not

involve any change in their composition.

y Chemistry deals with the study of changesin matter including structure, composition

and properties.

y Geology is the study of Earth structurey Astronomy is the study of heavenly

bodies and the universe.

y Meteorology deals with the study ofatmosphere, climate and weather.

y Mineralogy deals with the study ofminerals.

y Geography study of regional distributionof raw materials on the earth surface.

IMPORTANCE OF SCIENCE

It gives us an idea of the nature of lifeand the things around us

It explains the different phenomenaand eventually leads to discover of

general truth.

It becomes a source of intellectualenjoyment.

Through an understanding of scientificprocess, problem-solving and critical

thinking ability of the individual is

develop.

Science liberates the mind andsupplants superstitious beliefs and

prejudice.

LiMITATiONS OF SCiENCE

o Science cannot answer all types ofquestion.

o Science cannot answer questionsabout value.

o Science is dependent on the requiredtime in solving the problem.

o Science cannot answer questions ofmorality.

o Science has lack of absolute certaintyin the answer.

Lesson 1.2 Scientific Inquiry

Hypothesisis an intelligent or scientific guess based

on observation.

Theory is defined as an explanation of a phenomena

or a principle based on proven hypothesis, subjected to

multiple verifications conducted by researchers and

scientists.

Scientific Law is a precise and concise set of actions,

universally accepted to be true.

In science, the term Model refers to the illustrative

similitude of the steps or procedure to be taken in the

conduction of an experiment.

Scientific Method is a coherent and systematic

procedure of investigation. It is a reasoning process

which is used in the research for the relationships

among things and processes.

Scientific Method

1. Stating the problem

2. Gathering of data

3. Formulating a hypothesis

4. Experimentation

5. Recording and analyzing data

6. Drawing of conclusion and formulation of theory

7. Repeating the work



Theory is generalization that is accepted as true

because it is supported by facts.

Lesson 2.1 Forces and Newtons Laws of Motion

Force is simply defined as a push or pull. It is due to

interaction between objects and force exists because of

these interactions.

Force is a vector quantity.

The Four Basic Forces of Nature:

1. Strong Nuclear Force is the binding force between

nucleons.

Characteristics of strong nuclear force:

Charge Independence the nuclearforce between two protons is the same

as between a neutron and a proton.

Saturation the force needed to tear aneutron from a nucleus is

approximately the same regardless of

the number of nucleons in the nucleus.

Short Range the force decreasesrapidly with increasing distance.

2. Electromagnetic Force It is a force between

particles with electric charges.

The phenomenon has two differentcharacteristics:

Electrostatic Force is the force of two

electrically charged particles exerted is

force on one another.

This force between two charges is

directly proportional to the product of

the magnitude of the charges and

inversely proportional to the square of

the distance separating the charges.

. This law is known as

Coulombs law.

Magnetic Force the force due to the

motion of the charges.

3. Weak nuclear force it is the force responsible for

beta decay and other decay processes involving

fundamental processes.

4. Gravitational Force is an attractive force exerted on

a body by a highly massive object towards itself.

This formula represents the Universal Law of

Gravitation and G is the universal gravitation constant.

Weight is a force due to gravity.

Where g (earth) = gravitational

acceleration on earth = 9.8 m / sec2

= 32 ft / sec2.

Types of Forces:

1. Applied Force (Fapp) a force that is applied to an

object by another object.

2. Frictional Force (f) the force exerted by the surface

when an object moves across or tries to move across

the surface.

There are two main type of friction force:

Kinetic Friction is a force betweensurfaces of two bodies moving relative

to one another.

Static Friction is the force betweensurfaces of two non-moving bodies

relative to one another.

Pointers to be remembered about coefficient of

friction:

The smoother the surface, the lesserthe value of

The is smaller than. Frictional forces are directly

proportional to the normal force.

3. Normal Force (N) a force exerted by a stable objectupon an object in contact with.

4. Tensile Force (T) contact force exerted by a string,

rope or wire.

5. Spring Force (Fs) a force exerted by a stretched or

compressed string to an object attached to it.

6. Air Resistance (f air) the force exerted upon object

traveling through air.

7. Buoyant Force the upward force exerted by a fluid

on a submerged or floating object.

Isaac Newton is an English scientist who contributed

outstanding work in many areas of science.

Newtons Law of Motion:

1. Law of Inertia = an object at rest tends to stay at rest

and an object in motion will continue to move with the



same speed and in the same direction unless acted

upon by an unbalanced force.

Inertia is the natural tendency of an object to

resist changes in their state of motion.

2. Law of Acceleration = an object will accelerate if

there is net force acting to it.

Momentum (p) is the product of the mass and

the velocity of a body.

Impulse is the change in momentum.

3. Law of Interaction = for every action there is an equal

and opposite reaction.

Lesson 2.2 Work, Power, and Energy

Work is the product of the applied force (F) in the

direction of motion and the displacement (d) through

which the force acts.

Power is the time rate of doing work or expanding

energy.

Energy is the ability to do work, that is, it can cause

motion or changes.

Energy is a Scalarquantity it does not havedirection. Like work, the standard metric unit of

measurement for energy is theJoule.

Forms of Energy:

1. Mechanical Energy of a body or system is due to its

motion, its position, or its internal structure.

Two kinds of mechanical energy:

Potential Energy is the stored energy of thebody due to its position or its internal structure.

There are three kinds of potential energy:

Elastic potential energy is the energystored in a stretched or compressed

spring.

Internal / Chemical potential energy is the atomic and molecular energy of

matter as a result of their bonds and

interactions with each other.

Gravitational potential energy is thestored energy an object ha because of

its separation from the radius earth or

relative to a particular reference level.

Kinetic Energy is the energy stored due to themass and velocity of a body (waves, electrons,

atoms, molecules, substances, and objects) in

motion

Motion Energy is due to the movement of

substances and objects from one place to another.

There are different forms of motion energy:

vibrational (caused by vibrational force), rotational

(caused by rotational motion) and translational

energy.

The amount oftranslational kinetic energy

which an object has depends upon two variables:

mass (m) and the speed (v)

Conservation ofMechanical Energystatesthat the sum of the kinetic energy and potential

energy in a system is constant, if no resistance to do

work.

2. Nuclear Energy is the energy stored in the nucleus

of an atom. This energy can be released when the nucle

are combined (fusion) or split apart (fission).

3. Electrical Energy is the energy due to the

movement of the electrical charges.

4. Radiant Energy is due to electromagnetic waves

traveling as transverse wave. It includes light, x-rays,

gamma rays and radio waves.

5. Thermal energy or heat is the energy due to the

vibration and movement of the atoms and molecules

within the particles.

Sources of Energy:

1. Renewable energy source are sources that can be

replaced in a short period of time.

Types of renewable sources:

Biomass is energy from plants and animals. Itis rich in carbon and hydrogen that can be used

within the natural carbon cycle.

Solar Energy is the power from the sun, thusit is free and inexhaustible. Solar energy can be

converted to heat energy (for heating water in

the pool, homes, or buildings) and electricity



(usingphotovoltaic cellsor through solar power

plants).

Hydroelectric power uses the force of movingwater to produce electricity.

Geothermal Energy is the heat energyproduced from the earths core used for heating

buildings and to generate electricity.

Wind Power advanced aerodynamics researchhas developed wind turbines that can produceelectricity at a lower cost than power from

polluting coal plants. Cluster of wind machines

are called wind farms.

2. Nonrenewable energy source are limited and

cannot be replenished in a short period of time.

Types of non-renewable source:

Coal Energy is one of the largest sources fuelfor electricity but the largest source of

environmental harm.

Coal is a black brownish black

sedimentary rock, combustible and compost

mostly of carbons and hydrocarbons.

Natural Gas is a source of energy from fossils(organic materials) of plants and animals.

Propane is derived from processing

natural gas, which is commonly used in

the kitchen as fuel.

Petroleum (crude oil) is primarily used fortransportation fuels, also for power production,

heat and as feedstock for chemicals. Crude oil is

a smelly yellow-to-black liquid and is usuallyfound in underground areas called reservoirs.

Uranium is the most widely used fuel bynuclear power plants for nuclear power plants

for nuclear fission.

Lesson 2.3 Simple Machines

Simple Machine the simple components/tools used in

complex machines.

Effort is the force applied to the machine

Resistance is the force (friction and/or gravity)

overcome by the machine.

When a machine takes a small input force and increases

the magnitude of the output force, the machine

produces Mechanical Advantage (MA).

Hydraulic jackis a common tool designed to

make mechanical advantage.

*NOTE:

Guys yung sa page 35 diko na nilagay .

nalilito kc ako. Kayo nlang bahala e-review yun

huh Pati yung mga formula dun . thx .

Mechanical Simple Machines:

Lever it is the simplest machine. It is a simple log that

can multiply force and shift objects heavier than the

person holding the log.

Moment/torque is the turning effect

produced when an effort is applied to the lever to

rotate about a point (fulcrum). Its formula is

Torque = lever arm x effort

Levers are divided into three classes:

First-class Lever the fulcrum is locatedbetween the effort and the load.

Second-class Lever the fulcrum is at one endof the lever and the load is at the other end, the

effort is applied at the other.

Third-class Lever the fulcrum is at one end ofthe lever and the load is at the other end, the

effort is applied somewhere in between.

Wheel and Axle it is consists of a wheel rigidly

attached to an axle or shaft that turns the wheel.

Gears

are toothed wheel and axle. Gear trainis a series of intermeshing gears moving in opposite

directions.

Gear Ratio (IMA) can be computed by

Rack and pinion is another example of wheel

and axle. If the pinion is rotating in a fixed position, the

rack moves in linear motion.

Pulley it is a wheel pivoted so that it can rotate freely

about an axis through its center.

Fixed pulley is a first-class pulley with equal

lever arms.

Movable pulley is a second-class lever that

offers a gain in force.

Block is a pulley or group of pulleys in a frame

with a hook used for attaching. Tackle andfallare the

ropes or support. The individual wheels in the block are

sheaves.



Inclined Plane are slanted surfaces that help you

doing work.

Wedge is consists of two inclined planes set base to

base.

Screw it is a spiral inclined plane wrapped around a

cylinder.

Lesson 2.4 Heat: Chaotic Form of Energy

Temperature is the hot and cold of a body based on

our sense of touch.

Thermometer is a device that measures temperature

with some observable property, which varies, with

temperature.

Thermal Energy is the amount of energy measured

with a thermometer which represents the collectively

kinetic energy of the molecules moving within the

substance.

Types of Thermometer

Galilean thermometer is the first recordedinstrument for measuring temperature. A

change in temperature of the bulb gave rise to a

change in temperature in the water level in the

stem.

Mercury thermometer the length of mercurycolumn varies with temperature.

Alcohol thermometer Bimetallic Strip two different thin strips of

metal riveted together and spiraled, the outer

end anchored to the thermometer case and the

inner end attached to the pointer.

Resistance thermometer the electricresistance of a conductor changes with

temperature

Optical pyrometer measures very hightemperature.

Temperature Scales

Celsius Scale is commonly used in laboratory.It has 100 equal divisions called degrees. The

melting point of water was taken 0oC under

standard pressure while water boils at standard

pressure was taken to be 100oC.

Fahrenheitscale was name after GabrielDaniel Fahrenheit. The melting point of ice was

approximately 32oF while the boiling point of

water is 212oF.

Kelvin Scale Rankine scale is the absolute zero version of

the Fahrenheit scale.

When two substances with different temperatures

are placed in thermal contact, energy flows from

the hotter substance to the colder substance untilthey reach common temperature or equilibrium.

This energy is known as heat energy.

Internal energyof the substance is the sum of all

the energies inside a substance, molecular kinetic

energy and potential energy due to molecular

forces between particles in the substance.

Sources of Heat

1. Sun most important source of heat.

2.Earth it contains heat in it.

3.Chemical Reactions Oxidation and combustion

are chemical reactions that produce heat.

4.Nuclear Energy Can produce great amount of

heat.

5. Friction is usually unwanted source of heat

because it may damage things.

6.Electricity people use electricity to generate

heat that can be used to operate appliances and

machines.

Heat may cause:1. Changes in temperature

2. Changes in size heat is directly proportional to

the motion of the particles.

3. Changes in state

LatentHeatis the heat required to change a

substance from one state to another.

LatentHeat of vaporization is the energy

used to change liquid to vapor.

LatentHeat of condensation is energy

released when water vapor condenses to formliquid droplets.

LatentHeat of fusion describes both changing

from solid to liquid and from liquid to solid.

LatentHeat ofsublimation describes both

changing from solid to gas and gas to solid.

Transfer to Heat is normally from a high

temperature object to a lower temperature object.

CONDUCTION



Thermal Conduction is the flow of heat from a hot

part of a body to a cooler part, without transfer of

matter.

Thermal conductors substances that transfer heat

energy easily.

Thermal insulators substances that resist heat

transfer.

The ability of the substance to conduct heat ismeasured by thermal conductivityof the

substance.

CONVECTION

Convection ofHeat is the transfer of heat from

one place to another by motion of the heated

substance.

RADIATION

Radiation of heat is the transfer of heat energy in

the form of waves in the infrared region of the

electromagnetic spectrum.

Thermal Radiation is a type electromagnetic

radiation.

Radiation is a form of energy transport consisting

of electromagnetic waves traveling at the speed of

light.

Thermodynamics

Thermodynamics is a branch of science that is

concerned with the nature of heat and its

conversion to other forms of energy.

Four Classes of Thermodynamic System

1. Isolated System matter and energy may not cross

the boundary.

2.Adiabatic System heat and matter may not cross

the boundary.

3.Closed System matter may not cross the boundary;as time goes by, it tends to be in the state of

thermodynamic equilibrium.

4.Open System matter, heat and energy may cross

the boundary.

Thermodynamic Processes

1. Isobaric Process occurs at constant pressure

2.Isothermal Process occurs at constant temperature

3.Isochoric Process occurs at constant volume

4.Isentropic Process occurs at constant entropy

5.Adiabatic Process occurs without loss or gain of

heat

LAWS OF THERMODYNAMICS

1. Zero Law of Thermodynamics if system A and B are

in thermal equilibrium, and system B and C are

in thermal equilibrium, then A and C are alsothermal equilibrium.

2. First Law of Thermodynamics the increase of

energy added to the system by heating, Q,

minus the amount lost in the form of work done

by the system in its surrounding,W.

3. Second Law of Thermodynamics this law is about

the entropy, of the system. Entropy, S, is a

measure of disorder or randomness of a

system. This law is stated as follows:

The total entropy of any isolatedthermodynamics system tends to

increase over time, approaching a

maximum value.

A system operating in contact with athermal reservoir cannot produce

positive work in its surrounding LORD

KELVIN

A system operating in a cycle cannotproduce a positive heat flow from a

colder body to a hotter body CLAUSIUS

The entropy of a closed system neverdecreases MAXWELLs DEMON

4. Third Law of Thermodynamics the entropy of a

system at zero absolute temperature is a well-defined

constant.

- It can also state as all processes cease as temperature

approaches absolute zero.

Lesson 3.1 ATOMS: THE UNIT PARTICLES OF MATTER

Daltons Atomic Theory

* All matter consists of tiny particles calledatoms.

* Atoms cannot be created, destroyed,

subdivided or converted from one type to another.

* Atoms of a particular element all have the

same properties.

* Atoms of different elements have different

properties.

* Atoms combine in a simple whole number

ratio to form a combination of atoms called

compounds.



* A chemical change involves the joining,

separation or rearrangement of atoms.

Thomsons Model

The first subatomic particle was discovered by

Joseph Thompson, the electron. The first model of the

internal structure of the atom of the atom called the

plum-pudding model. An atom is a solid sphere of

positively charge matter (like the pudding) withnegatively charge electrons scattered throughout (like

the raisins of the pudding).

Rutherfords Model

Ernest Rutherford proposed that the positively

charged particles are not distributed throughout the

atom but are concentrated in the tiny area in the center

called nucleus. This is based on his work on thin gold

foil experiment.

The positively charged particle is called proton

by EugeneGoldstein.

According to Rutherford:

The atom consists of a small heavy corecalled nucleus.

The mass of the atom is concentrated in thenucleus.

The nucleus is surrounded by an electroncloud.

The atom as a whole is electrically neutral.James Chadwick discovered uncharged particles

called neutron.

Bohrs Atomic Model

According to Neils Bohr:

j The atom consists of stable stationary orbitswhere the electrons can revolve.

j The electrons are moving particles travelingin circular orbits at increasing distance from

the nucleus.

WAVE NATURE OF AN ELECTRON

De Broglie hypothesis an electron has dual properties,

that of a particle and a wave. De Broglie reasoned that if

light waves can behave like a stream of particles

(photon), then perhaps particle such as electron can

possess wave properties.

Lester Germer and Clinton Davission discovered that

electron could be diffracted.

Diffraction is the bending of waves around

small obstacles.

Erwin Schrodinger devised a mathematical model of an

atom using the wave properties of electrons and the

mathematical methods known as Wave mechanics. The

model is called Schrodinger equation.

FOUR QUANTUM NUMBERS

1. Principal Quantum number this tells us how far theelectron from the nucleus.

2.Azimuthal Quantum number this number refers to

the shape of the orbital (region in space where the

electrons are probably found).

3. Magnetic Quantum number this number tells us

the orientation of a particular orbital.

4. Magnetic Spin Quantum number tells us two

possible orientations of electrons in an atom.

LESSON 3.2 ELEMENTS, COMPOUNDS AND COMPLEX

MOLECULES

Element is the simplest of matter that contains one

kind of atom.

Molecules atoms are usually bound together, this is

the simplest unit of compound.

Two types of Compound:

1. Ionic compound

When a metal and a non-metal combine in a

chemical reaction, the resulting bond is ionic bond andthe resulting compound is an ionic compound.

2. Covalent Compounds

When two non-metals combine in a chemical

reaction, the bond formed is known as covalent bond

and the compound is called covalent compound.

Molecular Networks are composed of atoms linked by

continuous network of covalent bonds.

Diamond and Graphite are covalent-networksolids.

Diamondis bonded to four other carbon atoms.

This interconnected three-dimensional array of strong

carbon-carbon single bonds contributes to diamonds

unusual hardness.

Graphite is arranged in layers of interconnected

hexagonal rings.

Silicon dioxide is one of the constituents of

many minerals and gemstone. SiO2 is formed by strong,



directional covalent bonds, and has a well-defined local

structure.

Zachariesen-Warren modelfor the structure of

SiO2 shows that the tetrahedra formed by the SiO4groups must touch each other at their corners to form

network structure, but can do at widely varying angles.

MOLECULAR BALLS AND TUBES

Fullerenes are molecules composed entirely of

carbon, in the form of a hollow sphere, ellipsoid, tube,

or plane.

*BUCKYBALL is spherical fullerenes.

*BUCKMINSTERFULLERENCE is the smallest buckyball

and it is also called C60.

Carbon Nanotubes are cylindrical carbon molecule

with length-to-diameter ratio greater than 1,000,000.

The discovery of carbon nanotubes was credited to

Sumio Iijima in 1991.

LESSON 3.3 CHEMICAL TRANSFORMATIONS

Chemical Reaction is material transformation from a

beginning mass to a resulting substance.

The following are observations to indicate a chemical

reaction:

Change in color of the substance Evolution of gas Absorption Release of heat Formation of precipitate

Chemical Equation is a way to describe what goes on

in a chemical reaction, the actual change in a substance.

Ex.

The arrowpointing to the right indicates the direction

of the reaction. The substances to the left of the arrow

are Reactants

.T

he materials to the right of the arrowareproducts.

Reduction-oxidation (redox) reaction is a chemical

reaction that involves transfer of electrons from one

substance to another.

Reduction is a process wherein a substance accepts

electrons.

Oxidation is a process wherein a substance gives off

their electrons.

Oxidizing agents Substances which tend to gain

electrons.

Reducing agents Substances which tend to lose

electrons.

SOME COMMON REDOX CHEMICAL REACTIONS

COMBUSTION

Combustion or burning is a redox chemical

reaction that involves the reaction of the substance

with atmospheric oxygen when it is ignited.

Incomplete combustion produces carbon (as

soot) and carbon compounds, like carbon monoxide

(CO) and carbon dioxide CO2.

Burning of plastic, like PVC, produces

substances like Chlorinated dioxinsor simply dioxins.

Dioxins are carcinogenic, and directly

correlated with an increase in the l ikelihood of attaining

cancer.

Polystyrene (Styrofoam) when burn in an

open air produces organic pollutants like carbon

monoxide, PAHs (polycyclic aromatic hydrocarbons),

carbon black, and styrene monomer, which are harmfuland carcinogenic substances.

CORROSION

Corrosion is breaking down of essential

properties in a material due to chemical reactions with

its surroundings.

SEVERAL WAYS TO PREVENT RUSTING OF IRON:

1. Cover iron with paint2. Attach a more active metal

3. Mixing or coating the iron with another metal

whose oxide is structurally stable.

Zinc is usually used as a coating in a process

called galvanization.

Respiration is exothermic and provides the energy

that animals require in order to survive.



Photosynthesis is the process by which plants form

glucose; it is the reverse of respiration.

Chlorophylls it is the green pigments of the plant.

METABOLISM: CHEMICAL REACTION IN CELLS

Digestion the process of breaking down mechanically

or chemically into simpler compounds thecomplex compounds like carbohydrate,

proteins, and fats.

Enzymes are protein molecules that speed up

chemical reactions.

* Carbohydrates are converted into glucose

* Meat and other protein-rich is converted to

amino acid

* Fats are converted intofatty acid

Metabolism refers to the chemical reactions which

take place in the cells and tissues which are

important for the fulfillment of the vital

functions of a living organism.

Anabolism is a continuous balance between the

synthesis of complex compounds with the

consumption of energy.

Catabolism is the breakdown of complex molecules

with the release of energy.

*NOTE:Guys yung fate of carbohydrates,

Protein, tska fats dko n cnama .. nsa

may page 73 to 76 po .. nllito ako eih

(^.^v) basahin niu nlang bka masali din

yun sa exm eih

SOME HOUSEHOLD CHEMICALS AND THEIR REACTION

SYNTHETIC DETERGENTS: SURFACTANTS

Alkylbenzenesulfunatesis the first synthetic

detergent. These detergents were cheaper and

unlike soap they did not form curd. They form

micelle structure in water.

LinearAlkysulfunate a detergent wherein the

branched alkyl chain was replaced with straight

alkyl chain, just like soap. It decomposes

overtime forming CO2, H2O, and SO42-

which are

all found in the environment.

LAS andABS detergents are known as

anionic detergentsbecause the polar part of

the molecule I negative ion.

Researchers also developed cationic

detergentswhere the polar part is not ionic but

maintains polarity because of OH or other polar

groups.

BLEACHING AGENTS

Hydrogen peroxide is a colorless, rather unstable

liquid usually marketed as 3% solution in water.

Sodium hypochlorite (NaOCl) is found in household

bleach and is very strong oxidizing agent.

CREAMS AND LOTIONS

Cream and Lotionsare skin products that help the skin

maintain enough moisture.

* have emulsions of water and oil

* Lotion has more water than oil

* Cream has more oil than water

* contains emulsifying agents

* Some cream have additional ingredient like

titanium dioxide

SUNSCREEN

Sunscreens are usually lotions with additionalingredients to help absorb ultraviolet radiation.

UV light is classified into two:

UV-A extends from wavelength of 320

nm to 400 nm

UV-Bextends from 280 to 320 nm.

DEODORANT AND ANTIPERSPIRANTS

Deodorantsare designed to reduce body odor.

Triclosan an antibacterial agent that can kill bacteria

and thereby eliminate the odor that produced

by ammonia or hydrogen sulfide.

Antiperspirantreduces the amount of perspiration

that sweat glands produce. It contains

aluminum chlorohydrates.


10/10

ANTIOXIDANTS

Antioxidantsare substances that retard oxidation

process.

FOOD ADDITIVES AND COLORINGS

Monosodium Glutamate (MSG) is a salt of non-

essential amino acid, glutamic acid. It is whitecrystalline powder, when dissolved in water, it

dissociates to sodium and glutamic acid.

Umami unique taste of MSG.

Excitoxin is a chemical that damage and kill

nerve cells.

Sulfur dioxide it helps maintain the

appearance of the fruit and prevent the fruit

from rotting.

Nitrates and nitrites are primarily used for

preserving meat products such as longanisa,

tocino, sausages, ham, hotdogs, bacon and

corned beef.

Nitrosamines powerful carcinogens, which

combine with stomach acids and chemicals in

food.

Food Colorings are substances added to food

and beverages to change or enhance theircolors.

Artificialsweeteners are also common

additives in food products that we buy from

supermarkets. They duplicate the effect of

sugar or corn syrup in taste but usually have

less food energy.

Examples:

Aspartame is an artificial, non-saccharide sweetener and is about 200times as sweet as sugar with no caloric

value.

Saccharin is an artificial sweetenerwith effectively no food energy and is

about 300 times sweet as sucrose.

Sucralose is chlorinated sugar and600 times sweeter than sucrose.

*NOTE:

Kung may mali po sa reviewer na to pki

CORRECTnlang po marami yta 2ng kulang

ewn ko lang feeling lang (^.^v) dagdagan niu

nlang ..

GOODLUCK SA TESTBLOCKMATES!!!!

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