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The creation of sparks from metals is based on the pyrophoricity of small metal particles, and pyrophoric alloys are made for this purpose. [2] Practical applications include the sparking mechanisms in lighters and various toys, using ferrocerium; starting fires without matches, using a firesteel; the flintlock mechanism in firearms; and spark testing ferrous metals.
Effects depend on the substance; hydrogen peroxide removes a bleached layer of skin, while nitric acid causes a characteristic color change to yellow in the skin, and silver nitrate produces noticeable black stains. Chemical burns may occur through direct contact on body surfaces, including skin and eyes, via inhalation, and/or by ingestion.
The autoignition temperature or self-ignition temperature, often called spontaneous ignition temperature or minimum ignition temperature (or shortly ignition temperature) and formerly also known as kindling point, of a substance is the lowest temperature at which it spontaneously ignites in a normal atmosphere without an external source of ignition, such as a flame or spark. [1]
Others, particularly those used for crosslinking purposes, are much more stable and can be stored at normal ambient temperatures without risk of self-acceleration. Due to the large variations in the stabilities of peroxides, each is tested to determine the safe maximum temperature for which the peroxide may be stored, shipped, and handled.
When the amount of oxygen increases, the flame shortens due to quicker combustion, its color becomes a more transparent blue, and it hisses/roars. [2] With some exceptions (e.g., platinum soldering in jewelry ), the oxidizing flame is usually undesirable for welding and soldering, since, as its name suggests, it oxidizes the metal's surface. [ 2 ]
Accroides resin , higher burning rate than shellac, burns well even with potassium perchlorate. Suitable for chrysanthemum stars. When metallic fuels are used, the metal particle size is important. A larger surface area to volume ratio leads to a faster reaction; this means that smaller particle sizes produce a faster-burning composition.
Hydrogen peroxide is a chemical compound with the formula H 2 O 2.In its pure form, it is a very pale blue [5] liquid that is slightly more viscous than water.It is used as an oxidizer, bleaching agent, and antiseptic, usually as a dilute solution (3%–6% by weight) in water for consumer use and in higher concentrations for industrial use.
The Group 1 metal (M) is oxidised to its metal ions, and water is reduced to hydrogen gas (H 2) and hydroxide ion (OH −), giving a general equation of: 2 M(s) + 2 H 2 O(l) 2 M + (aq) + 2 OH − (aq) + H 2 (g) [8] The Group 1 metals or alkali metals become more reactive as their number of energy levels inceases.