Status Change of Water

Status Change of Water

Melting point and heat of fusion When heat is applied to ice (solid), the temperature rises gradually. By the way, while the ice is melting, the temperature does not rise. Temperature is kept constant, and the … more

Standard Reduction Potentials

Standard Reduction Potential

Standard hydrogen electrode A platinum electrode is inserted in a solution with a concentration of H+ of 1M, and hydrogen gas at 25℃ of 1 atm surrounding the platinum electrode is in equilibrium with H+. At … more

What if the water molecule have a straight structure?

What if the water molecule have a straight structure?

The structure of the water molecule Water is a representative ‘polar molecule’. The hydrogen-oxygen-hydrogen bonds that make up the water molecule have an angle of 104.5˚ and appear curved. Because of this unbalanced water molecule structure, … more

Polar Molecule & Nonpolar Molecule

Polar Molecule & Nonpolar Molecule

Polar molecule Polar molecules have polar covalent bonds between their constituent atoms, and the shape of the molecule is asymmetric. Therefore, the centers of positive and negative charges do not coincide. Just as there are poles … more

Law of Definite Proportions

Law of Definite Proportions 2

Lead iodide sediment formation reaction If you continue to add the lead nitrate solution to a certain amount of potassium iodide solution, the amount of sediment produced will continue to increase at the beginning and will … more

Heat Capacity

Heat Capacity

Heat capacity ‘Heat capacity’ is the amount of heat to raise the temperature of an object by 1℃. The heat capacity of an object is the specific heat of the object multiplied by the object’s mass. … more

Specific Heat

Specific Heat

Specific Heat When you apply the same amount of heat to metal and water of the same mass, the metal temperature change is greater than that of water. This is because the amount of heat required … more

Electrolysis of Water

Electrolysis of Water

Electrolysis of Water When electrolysis is performed using a dilute aqueous NaOH solution as an electrolyte, hydrogen gas is generated at the cathode (-), and oxygen gas is generated at the anode (+). The reaction equation … more

Graph of Charle's Law

Graph of Charle’s Law

Charle’s Law Charle’s Law In 1787, French scientist Charle (1746-1823) revealed that increasing the temperature of a gas by 1℃ at constant pressure increases the volume of the gas by 1/273 of the volume at 0℃. … more

Electric Plating

Electric Plating

Electric Plating Electroplating is a technique of depositing a thin film of another metal on the surface of a metal. (-) The electrode is connected to the object to be plated, (+) The electrode is connected … more

Chemical Cell (Voltaic Cell, Daniel Cell)

Chemical Cell (Voltaic Cell, Daniel Cell)

Electricity production before Volta Before chemical cells, such as dry cells, there was only one thing we knew as a way to produce electricity. That is rubbing amber, glass, or metal. Voltaic Cell Alessandro Volta (1745-1827) … more

Avogadro's Law

Avogadro’s Law

Avogadro’s Law The Italian scientist Avogadro (1776-1856) introduced the molecules’ concept to explain gases’ reactions. According to his theory, the volume of any gas at the same temperature and pressure is proportional to the molecules’ number. … more