أكاديميا - كولنز - معاجم الجيب العلمية - الكيمياء - انكليزي - فرنسي - عربي الحرف ٤_ d

Academia - Collins - Pocket Scientific Dictionaries - Chemistry - English - French - Arabic Letter 4_ D


double decomposition (or precipitation reactions)

double decomposition f

Decomposition (or precipitation reactions). You get this process
When anionic substances react in a solution. The result is an insoluble solid. For example:

CaCl + Na2CO3 → CaCO3 + 2NaCl
(aqueous) (solid) (aqueous) (aqueous)

Ca2+ + CO3 → CaCO3 or
(solid) (aqueous) (aqueous)

This is a method for preparing insoluble salts.


dry cell
pile in the room

Dry cell. The battery has a pasty electrolyte that does not leak out. The only wet battery in use today is the lead-acid accumulator.


dry ice
New color

Dry (carbonaceous) ice. Solid carbon dioxide. Because this substance sublimes, it is called dry. It is used to cool things (sublimation point = - 40° C), and is also used in theater to create smoke and clouds.


ductile
ductile

ductile. A ductile material can easily draw wires. For example, copper is a very ductile metal. The term is usually only used for metals. Ductile metals have large crystals inside them.
See annealing and malleable.


duralumin
duralumin m

Hard aluminum. An aluminum alloy containing copper (4) and small percentages of magnesium, manganese, manganese, and silicon. The mixture is much harder and stronger than pure metal and is used in making aircraft fuselages and cooking utensils.

dyes
colorants mpl

Pigments. Chemicals that can be mixed or reacted with other materials to make colored products, such as fabrics and plastics. Color is produced because the pigment absorbs some of the light that falls on it and reflects the rest of it.


dynamite
dynamite f

Dynamite is the explosive material invented by Alfred Nobel. Nobel had discovered that if a clay called Kieselger, or diatomaceous earth, absorbed an unstable explosive, nitroglycerin, the resulting explosive material would remain safe until it was deliberately detonated.
Nitroglycerin.