Part 2 Science Flashcards
anything that occupies space and has mass
MATTER
- are homogenous materials with definite chemical properties and consists of
one particular kind of matter.
PURE SUBSTANCES
- is a substance that can no longer be decomposed into simpler ones by ordinary
physical and chemical methods. There are at present 103 elements known. Of these, about 75
are metals and the remaining constitutes the non metals and the metalloids.
ELEMENT
How many elements are present?
How many metals are there?
103
75
During ordinary chemical changes, elements remain uncharged. However, not it is possible to
decompose or change an element into another by extraordinary methods. Some radioactive
elements like _____and ______ spontaneously decompose or disintegrate.
Radium and Uranium
CLASSIFICATION OF ELEMENT
Metal, Non-metal, Metalloid
-Base forming elements whose atoms can lose electrons and form positive ions. The
nomenclature commonly ends “ium” or “um”
Metals
Properties of Metals
a. usually solid (except Hg)
b. opaque, lustrous
c. malleable
d. ductile
e. conductors of heat and electricity
f. usually heavy except for a few
Examples of metals
Ca, Al, Na, Fe, Ag
- are acid forming elements whose atoms can gain electrons and form negative ions.
The names usually end in “gen” “ine” “on”.
Non-Metal
Properties of Non Metal
a. usually gases of brittle solid (except bromine)
b. mostly transparent
c. light
d. poor conductors of heat and electricity
l, Cl, H, He, Ru,
Non-Metal
Examples of Non-Metal
Examples: l, Cl, H, He, Ru,
- those elements which exhibit both metallic and non metallic properties.
Metalloids
Examples of metalloids
Examples
are antimony and arsenic
- composed of two or more elements chemically combined in a definite
proportion by weight
COMPOUND
Types of Compound
Organic
Inorganic
- any member of a large class of chemical compounds whose molecules
contain carbon
Organic compound
- any compound that does not contain carbon.
Inorganic compound
- compounds of oxygen and other elements
Oxides
*Inorganic
– compounds which contain hydrogen ions replaceable by metals. Example HCl, H2SO4,
HNO3
Acids
*Inorganic
– hydroxides of metals. Ex. NaOH. KOH
Bases
*Inorganic
– compounds which contain the negative radical of an acid and the positive radical of a
base
Salts
*Inorganic
Examples of inorganic
Ex. NaCl. CaBr2, CuSO4, Mg3(PO4)2
Have definite composition
Compound
Have variable composition
Mixture
Always homogeneous
Compound
Maybe homogeneous or heterogeneous
Mixtures
Have definite properties
Compound
Have variable properties depending on
the amount of components
Mixtures
The constituents are chemically combined
Compound
The components are not chemically
combined
Mixtures
The constituents may be separated
only by chemical means
Compound
the components may be separated by
physical or chemical means
Mixtures
Constituents are the particles that composed a _______
compound
Components are the particles that composed a _______
mixture
composed of two or more substances in a variable composition
Impure substance or mixtures
Mixtures are classified into:
Homogeneous
Heterogeneous
- composed of uniform composition and made up of only one phase
Homogeneous mixture
– a molecular or ionic dispersion of one substance in another. The particles in a
solution are too small that they can’t be seen by the naked eye even with the aid of ultra
microscope.
Solution
- do not have uniform composition
Heterogeneous mixture
- a mixture of whose particles are intermediate in size between a suspension and a
solution. The particles can be seen through an ultra microscope
Colloid
– These are coarse mixtures, particles are visible with the naked eyes and settle
out upon standing
Suspension
Properties of Matter
Physical and chemical properties
– those properties that may be received by the senses or measured by
physical means.
Physical Properties
- those properties involved when matter undergoes chemical changes
that is when a substance reacts with another substance.
Chemical Properties
Some chemical properties are:
- Stability towards heat, light and pressure
- Susceptibility to oxidation
- Reactions with water or acid or other substances
- Combustibility/Flammability
- Stability
- Relative Activity
- Ionizations
properties do not depend on the size or amount of the sample. Colors, odor, boiling
point, electrical conductivity are some examples
Intrinsic (intensive)
properties depend on the size or amount of the samples. Mass and volume are some
examples.
Extrinsic (extensive)
– is one in which the substance is changed in appearance, state or
properties but definitely not in composition.
PHYSICAL CHANGE
is the term applied to the change as solid turns into liquid
Melting
corresponds to the
reverse process in which liquid turns into solid.
Freezing
are terms applied to the change as liquid turns into gas.
Evaporation and vaporization
corresponds to the reverse process in which gas turns into liquid
Condensation
is the term applied to the changes as solid turns directly into gas.
Sublimation
refers to the reverse process in which gas turns directly in a solid.
Crystallization
is one in which the appearance as well as the composition of the
substances is changed resulting in one or more new substance/s. It is always accompanied by
energy changes.
CHEMICAL CHANGE
Reactions that absorb energy are said to be ________
endothermic
those that
release energy are _________.
exothermic
Electrolysis of water is an ________
endothermic reaction
burning is an _________
exothermic reaction.
– a molecular or ionic dispersion of one substance in another.
Solution
Physical properties example
- Color. Silver and copper may be recognized by their color
- Odor. Alcohol is easily differentiated from water by its odor. Hydrogen sulfide is easily
detected because of its foul odor, similar to rotten egg. - Taste. Sugar is sweet, salt is salty
- Solubility in water or other solvents. Sugar is very soluble in water while sand is insoluble
in water. - Physical states. Matter can exist in three physical states namely solid, liquid and gas.
- Density of Specific Gravity. Gases have low densities while solids have high densities.
- Index of Refraction. Diamond is distinguished from ordinary glass because of its high
refractive index. - Viscosity. Oil is more viscous than water
- Colligative properties. Melting point, boiling point, freezing point, vapor pressure, osmotic
pressure - Other properties like hardness, tensile strength, texture, electrical conductivity, shape, etc.
Physical properties example
Color
Odor
Taste
Solubility in water
Physical states
Density
Viscosity
Colligative properties
Other properties like conductibility, hardness, texture etc.
Carbon Dioxide, Carbides, Table Salts, Carbon Monoxide
Inorganic
Hydrogen, Oxygen, Nitrogen, Protein, Carbohydrates
Organic compound
