Avogadro's Law - In1811 the Italian physicist Amedeo Avogadro first proposed the idea that matter is made up of molecules and molecules are made up of atoms. In 1812, Avogado introduced a very important hypothesis to explain the law of Ga-Lussac, which is considered to be one of the major laws of chemistry today.According to the Avogadro rule, "at the same temperature and pressure, the same volume of gases has the same number of molecules."This rule led to the correct interpretation of Gai-Lussac's law.
InGa-Lamac-based 1811, Swedish scientist Bergelius introduced a hypothesis to explain the law of law which was based on Dalton's atomic theory. According to Bergelyus's hypothesis, the number of atoms in the same volume as gases at the same temperature and pressure.
Molecules : Matter is made of molecules and molecules are made of atoms. The smallest particles of a substance (element or compound) that can remain in free (free) state and have all the properties of that substance are called molecules. Normally, the diameter of molecules is between 44 to 206 and the molecular weight is from 2 to 1000. Proteins and molecules of many polymeric materials have a much larger size and molecular weight than simple molecules. Such molecules are called macromolecules. Larger molecules have a diameter of 50A to 250A or more and a molecular weight of 10,000 to several lakhs.
Mecular Weight:: Molecular weights are also relative weights of substances similar to the atomic weights of elements. "The molecular weight of a substance is the number it represents.
Recording of results of measurement - In Scientific work, accurate measurement of physical quantities and proper recording of their results is very important and important. Each measurement has some uncertainty that appears in the last digit of the recorded measurement. The last digit of the recorded measure indicates the estimated position and there is some uncertainty.
Refinement Congruence between : - The Two or more results of a measurement is called the precision of measurement. The precision of measurement depends on the proficiency of the person taking the measurement.
Accuracy -Accuracy between:the result of a measurement and the actual or valid value is called precision. The accuracy of a measurement depends mainly on the quality of the measuring instrument.
Significant marks : In a recorded measure, the digits which are known with certainty and the last numbered or indeterminate number are called meaningful digits.Significant points indicate the reliability of the measurement. The greater the number of meaningful digits in a recorded measure, the greater the confidence can be placed in that measurement. The measure in which the sum of meaningful digits is more is more accurate and the value in which the number of meaningful digits is less is less accurate.
Zero and meaningful points -counting the number of significant digits in the result of a measurement generally can see its value. For example, the measured length 25.7 cm has three significant digits and the measured length 5-216 cm has four significant digits, but what do the zeros measure in 0.0046 m, 0-008060 m, 70-010 m and 10-00 m etc. Will the count be in significant digits?
The following rules are related to whether the zeros present in the result of a measurement will be counted in meaningful: - The Digit Zero which only serves to determine the location of the decimal point is not counted as a meaningful digit. For example, only two meaningful digits in the number 0-0046 are the chemical base chemical equation -the substances (reactants) participating in a chemical reaction and the new substances (products) formed in that reaction with the help of symbols and formulas Display by "chemical equation". In the balanced chemical equation, the number of atoms of different elements is equal on both sides. Considerations displayed by chemical equations Every balanced chemical equation accurately describes a real chemical reaction. The balanced equation gives the following things.
(1) Chemical equations represent the reactants and products of the reaction and their composition.
(2) The equilibrium equation of the chemical reaction shows the relationship between the reactants and the quantities of the products (the number of moles) of the reaction, i.e. the stoichiometry of the reaction. The coefficients of the formulas of the reactants and products in the equilibrium equation represent the relative numbers of their moles (or molecules). These coefficients are called stoichiometry coefficients. The equilibrium equation represents the reaction ratio of the number of moles of the reactants and the products.
(3) In what proportion are reactants acting by weight and products are formed, it gives a balanced equation.
(4) By the Avogadro rule, under the same conditions of temperature and pressure, equal numbers of moles of gases occupy the same volume. At NTP, i.e. at 0 ° C and 760 mm pressure, 1 mole of any gas occupies a 22.4 liter volume. Therefore, if gaseous substances participate or are formed in the reaction, the coefficients in the equilibrium equation represent the ratio of their volumes.
Calculations based on stoichiometry equilibrium - The Chemical equation of a chemical reaction gives the relationship between the quantities of the reactants and the products. The relationship between the quantities of reactants and products is called stoichiometry of the reaction. The coefficients of the formulas of reactants and products in the equilibrium equation are called stoichiometry coefficients, and the quantities of reactants and products are called stoichiometry quantities. Calculations related to chemical reactions can be made with the help of balanced chemical equations. The coefficients in the equilibrium equation represent the relative numbers (stoichiometry ratios) of moles (or molecules) of the reactants and products.