The pH value of seawater changes in the morning and evening, and the pH value of seawater is more or

The pH of seawater generally varies in a range depending on the balance of carbon dioxide. Under the condition of constant temperature, pressure and salinity, the pH of seawater mainly depends on the ratio of various dissociation forms of H2CO3. When the buffering capacity of seawater is maximum, the pH should be equal to that of carbonate.

First, the second order of dissociation constants. Conversely, the concentration of carbonic acid can be estimated when the pH value of seawater is measured. When the salinity and total CO2 are constant, due to the carbonic acid section.

The first and second dissociation constants vary with temperature and pressure, so the pH value of seawater also changes. Calculate the carbonate at different temperatures and pressures.

First, the second level of dissociation constant value, you can calculate the pH. When measuring the pH of seawater in the laboratory, if the temperature and pressure are different from the on-site seawater, it needs to be corrected.

The pH value of seawater is a sign of the pH of seawater. The pH of seawater is greater than 7, so seawater is weakly alkaline. The pH of the sea varies depending on the season and the region:

In summer, due to warming and intense photosynthesis, the carbon dioxide content and hydrogen ion concentration in the upper layer of the sea water decrease, so that the pH value increases, i.e., the alkalinity increases, and in winter, the opposite is true, the pH value decreases. In areas with high dissolved oxygen, the pH is also high; Otherwise, the pH is low.

The pH of natural seawater is always stable.

Between 7 9 and 8 4.

The pH of unpolluted seawater is in between, which means that the natural ocean is a bit alkaline.

The average pH of the Pacific Ocean is.

The pH of seawater.

The pH value of seawater is about, and its value changes very little, so it is conducive to the growth of marine life; The weak alkalinity of seawater is conducive to marine bioavailability.

caCO3 composed of shells; Seawater.

The CO2 content is sufficient to meet the photosynthesis needs of marine organisms, so the ocean has become the cradle of life.

The pH of seawater.

It is a sign of the pH of seawater. The pH of seawater is greater than 7, so seawater is weakly alkaline. The pH of the sea varies depending on the season and the region:

In summer, due to warming and intense photosynthesis, the carbon dioxide content and hydrogen ion concentration in the upper layer of the sea water decrease, so that the pH value increases, i.e., the alkalinity increases, and in winter, the opposite is true, the pH value decreases. In areas with high dissolved oxygen, the pH is also high; Otherwise, the pH is low.

The pH of natural seawater is always stable.

Between 7 9 and 8 4.

The pH of unpolluted seawater is in between, which means that the natural ocean is a bit alkaline.

The average pH of the Pacific Ocean is.

The pH of the seawater is generally in between, the surface seawater is usually stable around the left, and the middle and deep seawater generally fluctuates between starvation.

The pH value of seawater is a measure of the pH of seawater. The pH of seawater varies depending on the season and region: in summer, the concentration of carbon dioxide and hydrogen ions in the upper seawater decreases due to warming and intense photosynthesis, so that the pH value increases, i.e., the alkalinity increases, while in winter, the pH value decreases.

In areas with high dissolved oxygen, the pH is also high, and vice versa, the pH is low.

Chemically, the pH and pH are used to indicate the state of an aqueous solution. These values can indicate what elements are dissolved in this solution.

The vast majority of pure water is water molecules (H2O), and a very small number of water molecules are ionized as hydrogen ions (H+) and hydroxide ions (OH-). Out of 500 million water molecules, only 1 water molecule is ionized.

The logarithmic value of the reciprocal of the concentration of hydrogen ions is pH. Pure water has a pH = 7 and is called neutral, with equal concentrations of hydrogen ions and hydroxide ions.

When pH <7, that is, the concentration of hydrogen ions in water is greater than that of pure water, it is acidic; It is alkaline when the pH >7, i.e., the concentration of hydroxide ions in the water is greater than that of pure water (see figure below).

Schematic diagram of the pH of seawater.

The pH = of surface seawater, which is the same in any sea, is weakly alkaline.

A certain amount of seawater is filled with a beaker and hydrochloric acid or phosphoric acid is slowly dropped, and the pH will slowly decrease. When the pH is less than 4, bubbles are generated. This bubble, like the bubbles in soda, is mainly made of carbon dioxide.

If alkaline soda or ammonia is dripped into seawater, the pH will rise (alkalize), and exposing it to air will absorb carbon dioxide.

The pH of surface seawater is stable around the same level because of the chemical equilibrium of bicarbonate ions (HCO-3), carbonate ions (HCO2-3) in seawater, and carbon dioxide in the air.

Of course, the pH of seawater is not eternal. When corals and coblithalgae grow, they absorb calcium carbonate and lower the pH of seawater, while the pH of the deep seabed increases due to the dissolution of calcium carbonate.

When phytoplankton photosynthesize, they consume carbon dioxide and the pH rises; When organic matter in the deep layers is decomposed, carbon dioxide is produced and the pH is reduced.

For example, the waters of the North Pacific Ocean at a depth of about 2,000 meters are very old, contain many decomposition products of organic matter, and the pH drops to almost neutral.

pH (vertical distribution) in the North Pacific and North Atlantic