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Water has a very high specific heat capacity of 4184 J/(kg·K) at 20 °C (4182 J/(kg·K) at 25 °C) —the second-highest among all the heteroatomic species (after ammonia), as well as a high heat of vaporization (40.65 kJ/mol or 2257 kJ/kg at the normal boiling point), both of which are a result of the extensive hydrogen bonding between its ...
The relative permittivity (in older texts, dielectric constant) is the permittivity of a material expressed as a ratio with the electric permittivity of a vacuum. A dielectric is an insulating material, and the dielectric constant of an insulator measures the ability of the insulator to store electric energy in an electrical field.
A perfect conductor has infinite conductivity, σ = ∞, while a perfect dielectric is a material that has no conductivity at all, σ = 0; this latter case, of real-valued permittivity (or complex-valued permittivity with zero imaginary component) is also associated with the name lossless media. [18]
A liquid dielectric is a dielectric material in liquid state. Its main purpose is to prevent or rapidly quench electric discharges.Dielectric liquids are used as electrical insulators in high voltage applications, e.g. transformers, capacitors, high voltage cables, and switchgear (namely high voltage switchgear).
Some of these properties are the high melting and boiling points (it is a liquid at room temperature), as well as the high dielectric constant and observable ionic dissociation. Hydrogen bonding in water also results in large values of heat and entropy of vaporisation, surface tension, and viscosity. [5]
Water vapor concentration for this gas mixture is 0.4%. Water vapor is a greenhouse gas in the Earth's atmosphere, responsible for 70% of the known absorption of incoming sunlight, particularly in the infrared region, and about 60% of the atmospheric absorption of thermal radiation by the Earth known as the greenhouse effect. [25]
Water is the most common and well-studied polar solvent, but others exist, such as ethanol, methanol, acetone, acetonitrile, and dimethyl sulfoxide. Polar solvents are often found to have a high dielectric constant, although other solvent scales are also used to classify solvent polarity. Polar solvents can be used to dissolve inorganic or ...
3 O +) and the concentration of hydroxide (OH −) are increased while the pH remains neutral. Specific heat capacity at constant pressure also increases with temperature, from 4.187 kJ/kg at 25 °C to 8.138 kJ/kg at 350 °C. A significant effect on the behaviour of water at high temperatures is decreased dielectric constant (relative ...