Write down what you know about the physical properties of water, one for each of the chemical proper

Physical properties of water :

Pure water is a colorless, odorless, tasteless, and transparent liquid. The freezing point of water is 0 and the boiling point is 100. Water is at its densest at 4 cm3. When water freezes, its density decreases and its volume expands.

Chemical properties of water:

Water and metal elements undergo redox reactions.

2H2O+2Na=2NaOH+H2, generally speaking, water reacts with active metals at room temperature to form alkali and hydrogen.

At high temperature, it can react with more active metals such as: mg+2h2o=mg(oh)2+h2 (the reaction needs to be heated).

Water reacts with non-metallic elements (mostly non-redox reactions).

cl2+h2o=hcl+hclo

2f2+2h2o=4hf+o2

Water reacts with oxides to form bases or acids.

so3+h2o=h2so4

na2o+h2o=2naoh

Water assists in the formation of acid salts:

caco3+h2o+co2=ca(hco3)2

Water reacts with peroxides and superoxides to produce oxygen.

2na2o2+2h2o=4naoh+o2

4ko2+2h2o=4koh+3o2

Water can hydrolyze with organic matter and inorganic salts

c12h22o11+h2o=c12h24h12

fecl3+3h2o＝fe(oh)3+3hcl

In general, it is a reversible reaction, but due to the heat of water dehydration, heating can promote hydrolysis, and under heating conditions, the above reaction can be carried out completely, and finally Fe2O3 is formed

Water is also capable of decomposing.

2H2O = 2H2+O2 (in the case of electrolysis or light).

Look for clear liquids.

Electricity decomposes into hydrogen and oxygen.

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Analysis: Physical properties of water :

Pure water is a colorless, odorless, tasteless, and transparent liquid. The freezing point of water is 0 and the boiling point is 100. Water is at its densest at 4 cm3. When water freezes, its density decreases and its volume expands.

The nature of the chemical excavation of water:

Water and metal elements undergo redox reactions.

2H2O+2Na=2NaOH+H2, generally speaking, water reacts with active metals at room temperature to form alkali and hydrogen.

At high temperature, it can react with more active metals such as: mg+2h2o=mg(oh)2+h2 (the reaction needs to be heated).

Water reacts with non-metallic elements (mostly non-redox reactions).

cl2+h2o=hcl+hclo

2f2+2h2o=4hf+o2

Water reacts with oxides to form bases or acids.

so3+h2o=h2so4

na2o+h2o=2naoh

Water can assist the limbs in the formation of acid salts

caco3+h2o+co2=ca(hco3)2

Water reacts with peroxides and superoxides to produce oxygen.

2na2o2+2h2o=4naoh+o2

4ko2+2h2o=4koh+3o2

Water can hydrolyze with organic matter and inorganic salts

c12h22o11+h2o=c12h24h12

fecl3+3h2o＝fe(oh)3+3hcl

In general, it is a reversible reaction, but due to the heat of water dehydration, heating can promote hydrolysis, and under heating conditions, the above reaction can be carried out completely, and finally Fe2O3 is formed

Water is also capable of decomposing.

2H2O = 2H2+O2 (in the case of electrolysis or light).

The physical properties of water are as follows:

1. It is a colorless and odorless liquid.

2. Boiling point: when the altitude is zero meters and the air pressure is one standard atmosphere, the boiling point is 100 degrees Celsius and the freezing point is 0 degrees Celsius;

3. The temperature at the maximum relative density is Celsius, the critical temperature is Celsius, and the density of ice is smaller than that of water;

4. Classification of water buoyancy: levitation, floating, sinking to the bottom, floating and sinking;

The chemical properties of water are as follows:

1. Relative molecular weight;

2. Molecular composition: composed of hydrogen atoms and oxygen atoms;

3. Stability: water begins to decompose above 2000 degrees Celsius;

4. Oxidation of water: when water reacts with more active metals or carbon, it shows oxidation, and hydrogen is reduced to hydrogen;

5. Electrolysis of water: water is decomposed to generate hydrogen and oxygen under the action of direct current, and pure hydrogen and oxygen are produced by this method in industry;

6. Hydration reaction: water can react with the basic oxides of active metals, most acidic oxides and some unsaturated hydrocarbons;

7. Hydrolysis reaction: salt hydrolysis, nitride hydrolysis, calcium carbide hydrolysis, etc.

The physical properties of water are as follows:

1. It is a colorless and odorless liquid.

2. Boiling point: when the altitude is zero meters and the air pressure is one standard atmosphere, the boiling point is 100 degrees Celsius and the freezing point is 0 degrees Celsius;

3. The temperature at the maximum relative density is Celsius, the critical temperature is Celsius, and the density of ice is better than that of water;

4. Classification of water buoyancy: levitation, floating, sinking to the bottom, floating and sinking;

The chemical properties of water are as follows:

1. Relative molecular weight;

2. Molecular composition: composed of hydrogen atoms and oxygen atoms;

3. Stability: water begins to decompose above 2000 degrees Celsius;

4. Oxidation of water: when water reacts with more active metals or carbon, it shows oxidation, and hydrogen is reduced to hydrogen;

5. Electrolysis of water: water is decomposed to generate hydrogen and oxygen under the use of lead in the direct current section, and pure hydrogen and oxygen are produced by this method in industry;

6. Hydration reaction: water can react with the basic oxides of active metals, most acidic oxides and some unsaturated hydrocarbons;

7. Hydrolysis reaction: salt hydrolysis, nitride hydrolysis, calcium carbide hydrolysis, etc.

1) The physical properties of water are:

1) It has three state changes: solid, liquid and steam. Its freezing point is 0, its boiling point is 100, and it exists as a liquid at room temperature. In production, it is to use the characteristics of water to change its morphology.

2) The volume of water is the smallest and the maximum ridge is at 4 (set at 1g cm3). Above or below this temperature, the density decreases and the volume increases. This is different from the law of thermal expansion and cold contraction of ordinary substances.

3) The specific heat of water is greater than that of all liquids and solid substances. Therefore, water is usually used as a medium for cooling or heat absorption.

4) The heat of evaporation (also known as the heat of vaporization) of water is the largest of all liquids. Reached at 100 at 1 atm).

5) When the ice melts, its heat capacity triples.

, and when the solid is melted, the change in heat capacity is very small.

6) When the water is boiling, the water temperature can still be kept at 100, and the water temperature of the ice-water mixture can still be kept at 0 when the ice is melted.

The pressure of water is related to temperature. If the pressure is constant, the boiling point is also certain, and when the pressure increases, the boiling point also increases accordingly, and the boiling point temperature of water under a certain pressure is also called the saturation temperature of water under this pressure.

8) Water has the general characteristics of liquids, so the water surface of each part is kept on the same plane under the condition of equal pressure.

9) Water has the greatest surface tension at room temperature (except for mercury), so it has.

Significant capillary phenomenon and lubrication.

2) The chemical properties of water are:

1) Stability of water.

Water can only decompose at high temperatures, indicating that the H-O bonds of water molecules are relatively firm, and it takes a higher energy to destroy them.

1000 or more.

2H20 is reversible 2H2+O2

2) Water energy reacts with certain exhibits and non-metals.

mg +2h, 0 heat mg (oh, +h2

C+H, 0 high temperature C0 ten H2.

3) Water can react with alkaline oxides to form alkali and acidic oxides to form acid.

h2o+cao=ca(oh)2

h2o+so,=h,so

4) Water can hydrolyze with certain salts.

h2o+al2(so)=h2so4+al(oh)

Physical properties of water :

Pure water is a liquid with no color, no smell, no taste. At 101kpa, the freezing point of water is 0 degrees Celsius, the boiling point is 100 degrees Celsius, and 4 degrees Celsius is the highest density of 1g cm3When water freezes, it expands in volume, so the density of ice is less than that of water and it can float on top of it.

Chemical properties of water:

1. Hydrogen and oxygen are produced by electrification 2H2O Energized 2H2 + O2

2. React with alkaline oxides to form alkali CaO+H2O ==Ca(OH)2

3. React with acidic oxides to form acid H2O + CO2== H2CO3

Uses: Water is one of the most common substances on the earth, an important resource for the survival of all life, including inorganic compounds, and human beings, and the most important component of living organisms. Water has played an important role in the evolution of life.

It is a narrowly non-renewable, broadly defined renewable resource.

Pure water can conduct electricity, but it is very weak (conductivity is negligible in daily life) and is a very weak electrolyte. Water in daily life has more positive and negative ions due to the dissolution of other electrolytes, and the conductivity is enhanced.