What is the information about water?

Hydrogen and oxygen. Two hydrogen atoms and one oxygen atom.

The composition of water has long been considered an elemental substance because it is difficult to break it down with ordinary heating methods. It was not until the end of the 18th century that scientists experimentally proved that water is a chemical compound.

What are the compounds that water is made of? There are two different ways we can do this.

Experiment 4-1] Fill the glass tube of the water electrolyzer with water, apply direct current, and observe the gas generated on the electrodes and in the glass tube and its volume. After a while, the gases in the two glass tubes were examined separately with a lit wooden strip.

Experiments have shown that when direct current is turned on, air bubbles are generated on the electrodes, and colorless gases are collected in the two glass tubes. The gas produced by connecting one end of the positive electrode is less than that produced by connecting the end of the negative electrode, and their volume ratio is about 1 2.

The small size of the gas can make the burning wood burn more vigorously, proving that it is oxygen.

The large volume of the gas, capable of combustion, is hydrogen.

The electrolysis of water produces hydrogen and oxygen, indicating that water is a compound composed of two elements, hydrogen and oxygen.

Experiment 4 2] Ignite the pure hydrogen produced from the hydrogen generating device. Insert the needle-nose catheter that ignites the hydrogen into a dry collection cylinder filled with oxygen (Figures 4-5). Take a closer look at the inner wall of the gas collector cylinder.

The inner wall of the dry gas collection cylinder is covered with a layer of water vapor, indicating that hydrogen reacts with oxygen to produce water. This reaction is expressed as follows:

Whether it's the electrolysis of water, or the combustion of hydrogen in oxygen, both experiments prove that water is indeed a compound composed of hydrogen and oxygen. After a large number of experimental measurements and scientific analysis, it has been confirmed that one water molecule is composed of two hydrogen atoms and one oxygen atom. The molecular formula of water is H2O.

The chemical reaction and the decomposition reaction were carefully analyzed and we found that the two reactions were not in the same form. The reaction that occurs in the electrolysis of water is the reaction of water to produce hydrogen and oxygen.

Chemically, the reaction of one substance to produce two or more other substances is called a decomposition reaction. When potassium permanganate is heated, oxygen, potassium manganate, and manganese dioxide are generated, which is also a decomposition reaction.

The experiment of hydrogen burning in oxygen to produce water is a substance that is formed by the reaction of hydrogen and oxygen.

Chemically, a reaction in which two or more substances react to form one other substance is called a chemical reaction. Magnesium is burned in the air to form magnesium oxide, which is also a chemical reaction.

Decomposition reactions and chemical reactions are the two most basic types of reactions in chemical reactions.

Water, in nature, is actually an alternative existence that breaks the convention. Scientists have summarized a total of 40 properties that distinguish water from other liquids. There are so many unanswered mysteries about water, and it can be said that water is the strangest substance in our universe.

70% of the human body is composed of water, the quality of water is related to the quality of human life, and now there are many new knowledge about water: 1, pure water is not nutritious, although it tastes good, but it cannot be used as long-term drinking water, 2, ionized water can only be used as medical treatment and can not be drunk for a long time, 3. The water quality of tap water is different in various places, and it is generally not allowed to be drunk for a long time, 3, and now the newly listed magnetized water is very good, which belongs to small molecule water, which is easy to enter human cells, easy to be absorbed, and is a good water that can be drunk for a long time, 4, the water in pollution-free fruits and vegetables is also the best water in the world, and it is also easy to be absorbed by the human body, and can be drunk every day.

If it helps you, please praise and thank you.

Purified water is not nutritious, and although it tastes good, it cannot be used as long-term drinking water.

Water includes natural water (rivers, lakes, atmospheric water, seawater, groundwater, etc.) and artificial water production (water obtained by combining hydrogen and oxygen atoms through chemical reactions). Water (chemical formula: H2O) is an inorganic substance composed of hydrogen and oxygen, which is a colorless and odorless transparent liquid at room temperature and pressure.

Water is one of the most common substances on Earth, an important resource for the survival of all life, including humans, and the most important component of living organisms. Water has played an important role in the evolution of life. Human beings have long begun to understand water, and water is regarded as a basic component in the ancient simple material concepts of the East and the West, and water is one of the five elements in ancient China. Water is also present in the ancient Western theory of the four elements.

The role of water. Water is the main component of the cells, and 60 70 nutrients and nitrogenous plants are dissolved in water to transport to their respective parts of the body.

When water is at 1 atmosphere (atm, 1 atmosphere) (kilopascals (kpa)), the temperature below 0 is solid (solid water), and 0 is the freezing point of water. From 0 to 100 is liquid (usually water appears liquid). More than 100 is a gas (gaseous water) and 100 is the boiling point of water.

The density of pure water is kilogram cubic meters at 0 and kilogram cubic meters at boiling point, and the density decreases by 4%. In 4 is the maximum density, with a density of 1000 kg cubic meters. The specific heat capacity of water is kg

c) Density of water: The density of water is the largest at 1 10m 3 kg, when the temperature is higher than (it can also be ignored as 4), the density of water decreases with the increase of temperature, at 0, the water heat shrinks and colds, and the density increases with the increase of temperature.

Water is the source of life, please cherish it and cherish it.

Now, China's resources have begun to decline: China's water resources are initially estimated at 2,711.5 billion cubic meters, and the average annual runoff from rivers and mountains is equivalent to the world's total runoff, while the per capita resource share is very low. China's natural resources are impressive in absolute terms, but their per capita share is lower than the world average.

How should we cherish resources?

Cherishing resources is something that everyone should do. How many people are cherishing resources? That's a lot, but there are many more people who are wasting resources. Why can't we do it? We can do it, it's just that we need to be more environmentally conscious.

Cherish resources and protect the environment, we can start from the small things around us, such as: do not litter, pay attention to saving water and electricity resources, do not use disposable items, etc., these are all ways to cherish resources. As long as we have perseverance, we will definitely be a small pacesetter who cherishes resources.

If the majority of people are destroying the environment, then the country will need to devote a lot of resources to clean up the environment. In this way, not only a lot of manpower is needed, but also a lot of material resources. But if we all become messengers of environmental protection, then we not only save resources, but also save human and material resources, and who wants to waste resources?

If most people waste water, then there will be no water to drink in the future, and even if there is, it will be precious. A newspaper once said that in about 70 years, water will be more expensive than oil.

The water flow also has a lot of energy. When a flood comes, it can tear down and submerge villages. People build various water conservancy projects, not only to prevent water disasters, but also to use the flow of water to serve the people. According to the survey, most of the world's hydropower resources are still unused.

Formation of water.

Perceptions of the origin of water are still widely divided, and there are currently about 32 theories about the formation of water. Here are a few of the main doctrines. One theory is that there was a primitive nebula of H2O molecules in the initial matter before the formation of the Earth, similar to the meteorites that now have an average water content, and that the Earth descended to the Earth after its formation, thus giving the Earth water.

Another theory holds that the original elements (hydrogen and oxygen) that formed water were formed only after the formation of the earth. Hydrogen and oxygen are combined under suitable conditions. Hydroxyl group (OH) is generated. The hydroxyl group then undergoes complex changes to form water (H2O).

The Dutch astronomer Ott believes that the main ** on Earth is the upper mantle of the lithosphere of the interior of our planet. Half of the lithosphere is made up of silicon, of which silicates and water. These rocks are dehydrated at a certain temperature and under suitable conditions, such as volcanic eruptions, thus forming the Earth's water.

American scholar John F. Kennedy and others believed that when the rock is completely mixed in melting, it contains 75% silicate and 25% water. In the early days of the Earth's formation, volcanic eruptions were frequent, which accelerated the formation of the Earth's water. The earth's water is increasing due to the high temperatures in the earth's interior.

In the study, there is data that the ocean level has risen in the last 1,000 years. However, the rapid rise of ocean levels in recent decades may be largely due to global warming.

The nature of water. Water, like other substances, increases in volume and decreases in density when heated. Pure water has a density of kilogram cubic meters at zero degrees Celsius and kilogram cubic meters at boiling point, with a density reduction of 4%.

At normal atmospheric pressure, when water freezes, the volume suddenly increases by about 11%. When the ice melts, it suddenly decreases in size. According to scientists' observations, in an enclosed space, when water freezes, it turns into ice, and the pressure generated by the increase in volume can reach 2,500 atmospheres.

This property is of great importance to nature and industry. This is why rock fissures gradually increase as they thaw repeatedly. The buried water conveyance plastic pipe is anti-freeze damage, and generally requires a certain buried depth (greater than the depth of the permafrost layer).

The freezing temperature of the water decreases as the pressure increases. For every 130 atmospheres of pressure increase, the freezing temperature of water decreases by 1 degree Celsius. This property of water makes it possible for the deep waters of the ocean not to freeze.

The boiling point of water varies in a linear relationship with the pressure. The boiling point increases with increasing pressure.

The heat capacity of water is higher than that of other substances, except that it is smaller than that of hydrogen and aluminum. Water has less heat transfer than other liquids. Due to this property, the ice body thickens slowly when the natural water body is frozen, and even when the water surface is frozen for a long time, the depth of the river may still be liquid, and this property of water is important for underwater life.

This property of water is also meaningful for guiding irrigation, for example, winter irrigation can increase ground temperature and prevent overwintering crops from low temperature frost damage.

Reference**.

Water (chemical formula: HO) is an inorganic substance composed of two elements, hydrogen and oxygen, and is non-toxic. It is a colorless and odorless transparent liquid at room temperature and pressure, and is known as the source of human life.

Water, including natural water (rivers, lakes, atmospheric water, seawater, groundwater, etc.), distilled water is pure water, artificial water (water obtained by combining hydrogen and oxygen atoms through chemical reactions). Water is one of the most common substances on the earth, an important resource for the survival of all life, including inorganic chemistry, 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.

Chinese name water. English name: water, oxidane, hydroxic acid, hydroxylic acid

Another name. Oxythane, hydrogen oxide (system nomenclature), hydronic acid, hydrogen hydroxide chemical formula HO

Molecular weight CAS accession number.

EINECs Login Number.

Melting point. 0℃(p0=

Boiling point. Folk custom called 100).

Water-soluble water has an affinity for a wide range of substances.

Density. 1g cm, 10 3kg m (t=4) appearance.

Colorless transparent liquid at room temperature.

Flash point. No flash point application.

solvents, life sustaining, electronics industry, etc.

Security description.

Safety hazard symbols.

Non-hazardous. Hazard description.

Non-hazardous. Dangerous goods transport number.

Specific heat capacity kj (kg· )

Three-phase point chemical properties are amphoterior.