The melting point of each element in the 3rd period.

Sorry, the landlord asked about the third cycle. I see the Lord. -

The melting point of the metal increases from Na to Si, because the melting point of the metal in the same period increases with the increase of charge, and because Si is an atomic crystal, the melting point is the highest, and then from P it is a molecular crystal, which is lower than both Si and metal, and S is lower, and the Cl2 and Ar in the back are both gases, so it is generally negative and lower.

The general trend is to increase from Na to Si and decrease from P to AR (P is divided into red and white, white is small and red is large).

The elements of the third cycle are not Na, Mg, Al, Si, P, S, Cl, and Ar

Eight kinds. These elemental elements are gaseous at room temperature, so the melting point is -200°. Cl is also gaseous and below 0°, the periodic table is regular, the same period, the melting point is reduced at one time, the maximum melting point is Na, the principle, because the outermost electrons are few, the greater the van der Waals force between molecules, then the higher his melting point. Thank you.

Sodium: Magnesium:

Aluminum: Silicon: 1410

Phosphorus: white phosphorus, red phosphorus, 590

Sulfur: Chlorine: Argon:

1. With the increase of atomic number of elements in the same period, the melting point of the metal element of the element increases, and the melting point of the non-metal element decreases;

2. From top to bottom, the melting point of the metal element composed of the elements decreases, and the melting point of the non-metal element increases.

The melting and boiling point of alkali metals in the first main group is determined by the bond energy of the metal, and in the case of the same charge, the smaller the atomic radius, the greater the bond energy of the metal, so the melting and boiling point of alkali metals is determined by the melting and boiling point from top to bottom.

The halogens of the seventh main group, its elemental element is molecular crystals, so the melting and boiling point is determined by the intermolecular force, in the case of similar molecular composition, the greater the relative molecular mass, the greater the intermolecular force, so the melting and boiling point of halogens is gradually changed by the boiling point from top to bottom.

Melting point of elemental matter:

1. With the increase of atomic number of elements in the same period, the melting point of the metal element of the element increases, and the melting point of the non-metal element decreases; 2. From top to bottom, the melting point of the metal element composed of the elements decreases, and the melting point of the non-metal element increases.

This should be aimed at the element, and the law depends on what crystal type the elemental belongs to to be judged.

1. For substances with different crystal types, generally speaking: atomic crystals, ionic crystals, molecular crystals, and metal crystals have a wide range of melting points.

2. Atomic crystal: the shorter the bond length and the greater the bond energy of the atomic crystal, the more stable the covalent bond is, the higher the melting and boiling point of the substance, and vice versa. Such as:

Diamond (C—C) Silicon Carbide (Si—C) Crystalline silicon (Si—Si).

3. Ion crystal: The smaller the anion and cation radius and the higher the charge number in the ion crystal, the stronger the ionic bond, the higher the melting and boiling point, and vice versa.

Such as kf kcl kbr ki, cao kcl.

4. Metal crystal: the more the number of valence electrons of the metal atom in the metal crystal, the smaller the atomic radius, and the more the electrostatic interaction between the metal cation and the free electron.

Strong, the stronger the metallic bond, the higher the melting boiling point, and vice versa. Such as: na mg al.

5. Molecular crystal: the greater the intermolecular force of the molecular crystal, that is, the greater the relative molecular mass, the higher the melting and boiling point of the substance, and vice versa.

Therefore, it depends on what kind of substance it is, for example, IA elemental is a metal crystal, and the melting and boiling point of their elemental element gradually decreases from Li to CS; For example, VIIA elements are molecular crystals, and the melting and boiling points of their elements gradually increase from F2 to I2.

Same as the main family. Metal: from top to bottom, gradually decreasing; Non-metallic: from top to bottom, gradually rising;

Same period. metal, from left to right, gradually rising; Non-metallic, from left to right, gradually decreasing.

The metal with the highest melting point in the element composed of the element of the third cycle, aluminium AL

The nature of al.

Condition: Silvery, lightweight, non-magnetic malleable metal Melting Point ( ) Boiling Point ( ) 2467 Density (G Disturbance CC, 300K):

Specific heat j gk : heat of evaporation kj mol : heat of melting kj mol:

Electrical conductivity 106 cm: Thermal conductivity w cmk:

Na's. Condition: Soft, silvery-white alkaline metal. Melting point ( ) 98 Boiling point ( ) 883 Density (g cc, 300k):

Specific heat j gk : heat of evaporation kj mol : heat of melting kj mol:

Electrical conductivity 106 cm: Thermal conductivity w cmk:

mg. Condition: Light gray metallic. Melting point ( ) 649 Boiling point ( ) 1090 Density (g cc, 300k):

Specific heat j gk : heat of evaporation kj mol : heat of melting kj mol:

Electrical conductivity 106 cm: Thermal conductivity w cmk:

1.Periodicity: Within the same period, usually, the melting point increases with the increase in atomic number.

This is because as the atomic number increases, the positive charge of the nucleus also increases, and the attraction of electrons to the nucleus increases, making it more difficult for the atom to break away from the solid to form a liquid state.

2.Atomic size: In the same period, elements with relatively large atomic size have lower melting points, because large atomic size means that the electron cloud is widely distributed around the nucleus, and the attraction between electrons and nuclei is weak, and it is easy to form a liquid state.

3.Element Type: Metallic elements usually have a lower melting point because metallic elements have a good metallic structure and metallic bond strength, which allows metallic elements to melt at relatively low temperatures.

Non-metallic transport elements usually have a higher melting point because non-metallic elements usually exist in the form of covalent bonds with weak structure and bond strength and require higher temperatures to break the bonds and melt them.

There are many other factors that may affect the melting point of an element, such as pressure, lattice junction, chemical bond type, etc.