Answer:
Iodine have higher atomic size than tellurium because of the presence of more number of protons and lower atomic mass than tellurium because of the presence of lower number of neutrons.
Explanation:
Atomic number of an element is the number of the protons present in the element.
Atomic mass is the sum of a protons and the neutrons which are present in the nucleus of the atom.
Iodine has higher atomic number than tellurium because it has more number of protons than the tellurium.
On the other hand, iodine has lower atomic mass than tellurium because it has less number of neutrons in its core.
Answer:
La tabla periódica de moseley fue una manera de dar solución a esta problemática, ya que nos permite tener a la mano todos los elementos que se han descubierto hasta la actualidad y sus propiedades químicas más resaltantes.
A continuación se Describe una linea del tiempo de la creación de la tabla periodica:
1820 - se crean las tríadas de Dobereiner.
1863 - se crea el cilindro de chancourtois.
1864 - se crean las octavas de newlands.
1869 - se crea el primer prototipo de la tabla periódica.
1914 - se fórmula la ley periódica moderna por Moseley.
Explanation:
The correct option is; SUGAR DISSOLVING IN WARM WATER.
There are two types of change in chemistry; physical and chemical changes.
A physical change is a type of change in which no new substance is formed while a chemical change is a type of change in which a new substance is formed.
Dissolving sugar in warm water is a physical change because no new substance is formed and the sugar can easily be recovered from the water by evaporating the water.
There are many ways which can <span>lead us to believe a chemical reaction has occurred. I am discussing few of them.
Change in Color:
Few reactions proceed with the change in colour. When Bromine Water (yellow-Brown) is treated with unsaturated compounds, the color disappear as the reaction is completed.
Gas Production:
Some reactions proceed with the elimination of gas i.e. CO</span>₂ , H₂, N₂, H₂O e.t.c.
Temperature Change:
Some reactions evolve or absorb heat when proceed. This change is the evidence of progress of reaction.
Thin Layer Chromatography:
Very important technique in detecting the progress of reaction by determining the number of spots for UV active compounds on TLC plate. Even non UV active compounds can be detected by using other locating agents.
Instrumental Techniques:
Modern techniques like IR, MS, NMR, UV spectroscopy can be used to detect the progress of reaction.
