- •Chemistry
- •Introduction
- •Some facts about chemistry
- •Some facts about atoms (I)
- •Some facts about atoms (II)
- •The atomic model
- •The nature of ceramics
- •Construction materials
- •The measurements in chemistry
- •The metric system
- •Isotopes
- •Words to be remembered:
- •Notes on the text:
- •Liquids(I)
- •Words to be remembered:
- •Liquids (II)
- •Words to be remembered:
- •Solid state (I)
- •Words to be remembered:
- •Solid state (II)
- •Words to be remembered:
- •Properties of solids
- •Notes on the texts:
- •Words to be remembered:
- •Organic chemistry
- •Word to be remembered:
- •Elementary carbon
- •Words to be remembered:
- •Notes on the texts:
- •Carbon dioxide
- •Words to be remembered:
- •Words to be remembered:
- •Hydrogen
- •Words to be remembered):
Words to be remembered:
nucleus chlorine
as well as ratio
contain identical
considerably approach
extreme case
Notes on the text:
odd atom - лишний атом
in the case of uranium - если мы имеем дело с ураном (в случае с ураном) regular atoms - обычные атомы
e.g. = for example - например
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Liquids(I)
She liquid state occupies an intermediate position between the gaseous and solid spates, liquid having a definite volume but no definite shape.
Like a gas, a liquid can take the shape of any vessel in which it is put, but in contrast to a gas, a definite quantity of liquid is required for filling the vessel. A liquid can not be compressed so much as a gas because its molecules are already close together, large pressure producing small changes in volume.
Increasing the temperature increases the kinetic energy of all molecules.
The change of a liquid into a gaseous or liquid states being dependent upon the kinetic energy of the molecules, which in turn is dependent upon the temperature, there are definite temperature characteristics for most liquids at which these changes occur. They are known as transition temperatures.
If we place one liquid layer carefully on top of a layer of a more dense liquid in which it is soluble, and set the vessel where it won’t be disturbed, we shall see that two liquids begin gradually mixing. It is also to be taken into consideration
that all liquids do not flow with the same ease, water, alcohol, gasoline flowing easily, while heavy oil glycerin flowing very slowly.
When a liquid flows, layers of molecules begin rubbing over each other о friction being generated by this rubbing of layers of particles. The greater the friction, the slower is the flow. A liquid which resists flowing, or resists the reaction of any other deforming force upon it results in a homogeneous solution. We give this example for illustration that the molecules of a liquid diffuse, though much slowly than do those of a gas.
The molecules of a liquid are much closer together than they are in a gas, because of the greater relative strength of attraction, the density of liquids being much greater. Naturally as the volume of a liquid begins varying with temperature its density will also start varying with temperature.
It should be noted that the closeness of the molecules also is known as viscous, the opposite of viscosity being fluidity. Viscosity diminishes and fluidity increases with temperature.
Words to be remembered:
intermediate soluble
shape gradually
vessel to flow
to compress gasoline
to increase rub
dependent friction
transition viscosity
layer fluidity
dense in turn
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