Sudut Pameran Kimia KMM

1

Nikotinamida adenina
dinukleotida

Nicotinamide adenine dinucleotide (NAD) is C21H27N7O14P2

a cofactor that is central to metabolism. Found in all living cells, NAD is 663.43 g/mol
called a dinucleotide because it consists of two nucleotides joined through
their phosphate groups. One nucleotide contains Difosfopiridina nukleotida
an adenine nucleobase and the other nicotinamide. NAD exists in two (DPN+) , Koenzim I
forms: an oxidized and reduced form, abbreviated

as NAD+ and NADH respectively.

In metabolism, nicotinamide adenine dinucleotide is involved
in redox reactions, carrying electrons from one reaction to another. The
cofactor is, therefore, found in two forms in cells: NAD+ is an oxidizing
agent – it accepts electrons from other molecules and becomes reduced.
This reaction forms NADH, which can then be used as a reducing agent to
donate electrons. These electron transfer reactions are the main function
of NAD. However, it is also used in other cellular processes, most notably
a substrate of enzymes that add or remove chemical groups from proteins,
in posttranslational modifications. Because of the importance of these
functions, the enzymes involved in NAD metabolism are targets for drug
discovery.

Chemical structure

Molecule Model

2

Sucrose

Sucrose is common sugar. It is a disaccharide, a molecule C12H22O11

composed of two monosaccharide: glucose and fructose. Sucrose is pro- 342.30 g/mol
duced naturally in plants, from which table sugar is refined. It has β-D-Fructofuranosyl α-D-
glucopyranoside
the molecular formula C12H22O11.
Chemical structure
For human consumption, sucrose is extracted, and refined, from ei-
ther sugar cane or sugar beet. Sugar mills are located where sugarcane is
grown to crush the cane and produce raw sugar which is shipped around
the world for refining into pure sucrose. Some sugar mills also process the
raw sugar into pure sucrose. Sugar beet factories are located in colder cli-
mates where the beet is grown, and process the beets directly into refined
sugar. The sugar refining process involves washing the raw sugar crystals
before dissolving them into a sugar syrup which is filtered and then passed
over carbon to remove any residual colour. The sugar syrup, by now clear,
is then concentrated by boiling under a vacuum and crystallized as the final
purification process to produce crystals of pure sucrose. These crystals are
clear, odourless, and have a sweet taste. En masse, the crystals appear
white.

Sugar is often an added ingredient in food production and food recipes.
About 185 million tonnes of sugar were produced worldwide in 2017.

Molecule Model

3

Phosphoric Acid

Phosphoric acid (also known as orthophosphoric acid or phosphoric H3PO4

(V) acid) is a weak acid with the chemical formula H3PO4. Orthophosphor- 97.994 g/mol
ic acid refers to phosphoric acid, which is the IUPAC name for this com- OrthoPhosphoric acid
pound. The prefix ortho- is used to distinguish the acid from related phos-
phoric acids, called polyphosphoric acids. Orthophosphoric acid is a non-
toxic acid, which, when pure, is a solid at room temperature and pressure.
The conjugate base of phosphoric acid is the dihydrogen phos-
phate ion, HPO42-, which in turn has a conjugate base of hydrogen phos-
phate, HPO42-, which has a conjugate base of phosphate, PO43-. Phos-
phates are essential for life, being building blocks for both DNA and RNA.

The most common source of phosphoric acid is an 85% aqueous solution;
such solutions are colourless, odourless, and non-volatile. The 85% solu-
tion is a syrupy liquid, but still pourable. Although phosphoric acid does
not meet the strict definition of a strong acid, the 85% solution can still
severely irritate the skin and damage the eyes

Chemical structure

Molecule Model

4

Sulfuric Acid

Sulfuric acid (alternative spelling sulphuric acid), also known as vitriol, H2SO4

is a mineral acid composed of the elements sulfur, oxygen and hydrogen, 98.079 g/mol
with molecular formula H2SO4. It is a colorless, odorless, and syrupy liquid Sulphuric acid
that is soluble in water and is synthesized in reactions that are highly exo-
thermic. Chemical structure

Its corrosiveness can be mainly ascribed to its strong acidic nature, and, if
at a high concentration, its dehydrating and oxidizing properties. It is al-
so hygroscopic, readily absorbing water vapor from the air. Upon contact,
sulfuric acid can cause severe chemical burns and even secondary thermal
burns; it is very dangerous even at moderate concentrations.

Sulfuric acid is a very important commodity chemical, and a nation's sulfu-
ric acid production is a good indicator of its industrial strength. It is widely
produced with different methods, such as contact process, wet sulfuric acid
process, lead chamber process and some other methods.

Sulfuric acid is also a key substance in the chemical industry. It is most com-
monly used in fertilizer manufacture, but is also important in mineral pro-
cessing, oil refining, wastewater processing, and chemical synthesis. It has
a wide range of end applications including in domestic acidic drain clean-
ers, as an electrolyte in lead-acid batteries, in dehydrating a compound,
and in various cleaning agents

Molecule Model

5

Water

Water (H2O) is a polar inorganic compound that is at room tempera- H2O

ture a tasteless and odorless liquid, which is nearly colorless apart from an 18.01528 g/mol
inherent hint of blue. It is by far the most studied chemical compound and water, oxidane
is described as the "universal solvent" and the "solvent of life". It is the
most abundant substance on Earth and the only common substance to
exist as a solid, liquid, and gas on Earth's surface. It is also the third most
abundant molecule in the universe.

Water molecules form hydrogen bonds with each other and are strongly
polar. This polarity allows it to dissociate ions in salts and bond to other
polar substances such as alcohols and acids, thus dissolving them. Its hy-
drogen bonding causes its many unique properties, such as having a solid
form less dense than its liquid form, a relatively high boiling point of 100 °C
for its molar mass, and a high heat capacity.

Water is amphoteric, meaning that it can exhibit properties of an acid or a
base, depending on the pH of the solution that it is in; it readily produces
both H+ and OH− ions. Related to its amphoteric character, it undergoes self
-ionization. The product of the activities, or approximately, the concentra-
tions of H+ and OH− is a constant, so their respective concentrations are
inversely proportional to each other.

Chemical structure

Molecule Model

6

Ammonia

Ammonia is a compound of nitrogen and hydrogen with NH3

the formula NH3. A stable binary hydride, and the simplest pnictogen hy- 17.031 g/mol
dride, ammonia is a colourless gas with a characteristic pungent smell. It is Trihydridonitrogen
a common nitrogenous waste, particularly among aquatic organisms, and it Nitrogen trihydride
contributes significantly to the nutritional needs of terrestrial organisms by
serving as a precursor to food and fertilizers. Ammonia, either directly or
indirectly, is also a building block for the synthesis of many pharmaceutical
products and is used in many commercial cleaning products. It is mainly
collected by downward displacement of both air and water. Ammonia is
named for the Ammonians, worshipers of the Egyptian god Amun, who
used ammonium chloride in their rituals.

Although common in nature—both terrestrially and in the outer planets of
the Solar System—and in wide use, ammonia is
both caustic and hazardous in its concentrated form. It is classified as
an extremely hazardous substance in the United States, and is subject to
strict reporting requirements by facilities which produce, store, or use it in
significant quantities.

Chemical structure

Molecule Model

7

Diamond Cubic

Diamond's cubic structure is in the Fd3m space group, which follows

the face-centered cubic Bravais lattice. The lattice describes the repeat pattern;
for diamond cubic crystals this lattice is "decorated" with a motif of
two tetrahedrally bonded atoms in each primitive cell, separated by 1/4 of the
width of the unit cell in each dimension. The diamond lattice can be viewed as a
pair of intersecting face-centered cubic lattices, with each separated by 1/4 of
the width of the unit cell in each dimension. Many compound semiconduc-
tors such as gallium arsenide, β-silicon carbide, and indium antimonide adopt
the analogous zincblende structure, where each atom has nearest neighbors of
an unlike element. Zincblende's space group is F43m, but many of its structural
properties are quite similar to the diamond structure.
The atomic packing factor of the diamond cubic structure (the proportion of
space that would be filled by spheres that are centered on the vertices of the
structure and are as large as possible without overlapping)
is π√3/16 ≈ 0.34, significantly smaller (indicating a less dense structure) than
the packing factors for the face-centered and body-centered cubic lattic-
es. Zincblende structures have higher packing factors than 0.34 depending on
the relative sizes of their two component atoms.
The first-, second-, third-, fourth- and fifth-nearest-neighbor distances in units
of the cubic lattice constant are √3/4, √2/2, √11/4, 1 and √19/4, respectively.

Molecule Model Visualisation of a diamond
cubic unit cell:

1. Components of a unit
cell,

2. One unit cell,

3. A lattice of 3 × 3 × 3 unit