Stoichiometry
Understanding Stoichiometry
Stoichiometry comes from two languages ie the
language meaning "element" and Metron which means
"measurement".
Stoichiometry is a subject in chemistry involving the
linkage of reactants and products in a chemical reaction to determine the
quantity of each substance that is resistant. Or usually Stoichiometry is a subject in chemistry that
studies the quantity of matter in a chemical reaction.
Before performing Stoichiometric calculations, the equation of the reaction we have must be equalized first.
Equalization of Chemical Reaction
Chemical reactions are often written in the form of equations using elemental symbols. The reactants are the substances that are on the left, and the product is the substance that is on the right, then both are separated by arrows (can be one or two alternating arrows).
Example:
2Na(s)+HCl(aq)→2NaCl(aq)+H2(g)
The equation of a chemical reaction is like a prescription in the reaction, thus indicating everything associated with the reaction, whether it is an ion, an element, a compound, a reactant or a product. All. Then as in the recipe, there is a proportion of the equation shown in the figures in front of the molecular formula.
Basic Stoichiometric Solution The term "concentration" of the solution expresses the amount of solute dissolved in a certain amount of solvent or a certain amount of solution. The concentration of the solution can be expressed in molarity. Molarity (M) is defined as the number of moles of solute per liter of solution.
Basic Ideal Gas Stoichiometry The molar volume, Vm, is defined as the volume of 1 mol entity (atom, ion, molecule, unit of formula) of matter. The unit of the molar volume (Vm) is L / mol.
PV = n RT
Avogadro's law states that at certain pressures and temperatures and fixed, the volume of the gas is directly proportional to the amount of gas.
CONCEPT MOL
The relationship of Moles to the number of particles
Number of particles = mol x 6,02 x 10˄23
Mol = Number of particles / 6,02 x 10˄23
Relation of Moles to Mass
For element:
· Mol = grams / Ar
· Grams = mol x Ar
For compounds :
· Mol = grams/Mr
· Grams = mol x Ar
Relation of Mole to Gas Volume Every mole of gas of any standard state (0oC, 1 atm) has a volume of: 22.4 liters.:
· Volume of gas = mol x 22,4
· Mol = Volume / 22,4
Please explain the laws that govern the stoichiometry!
BalasHapus
HapusThe Law of Conservation of Mass
The law of mass conservation was first proposed by Lomonov and Antoine Lavoisier rediscovered (both unrelated). This law explains that all reactions, in closed systems, of mass of substances before and after the reaction are the same. Nothing was created or destroyed. Everything is just a new combination. Lavoisier conducted the following experiments. He heats a piece of lead in a sealed tube. Gray ash appears on the tin surface. He heated it for a day and a half until the ashes did not appear. Then, he weighs the mass of the tin-covered tube before being burned with a burned tube (which contains lead oxide, tin left, and oxidized air). The result, he found that the mass before and after the reaction is the same.
Fixed Comparison Law
Comparative law is still found by Joseph Proust, a French chemist. Comparative law still states, as the name implies, the ratio of the mass of elements in a compound is certain and fixed. Thus, any compound anywhere must consist of a definite mass ratio. For example, the ratio of sodium and chlorine mass to NaCl by 2 grams is 0.768 grams and 1,124 grams. Then the mass ratio is 1: 1.54 or simplified 2: 3. If the same compound is taken from another source of 2.5 grams with sodium 0.983 gram, it is found 0.983: 1.517 or 1: 1.54 or 2: 3.
Multiple Multiple Laws
At the time of this law, the chemical formula of the compound is unknown. This law was put forward by John Dalton, a British chemist and inventor of modern atomic theory. This law states that if the mass of one element in two compounds is equal, then the ratio of the mass of the other elements is a simple integer. For example, the ratio of carbon (C) and oxygen (O) elements to sequential carbon monoxide and carbon dioxide is 3: 4 and 3: 8. If the mass of C is equal, then the ratio of mass O to carbon monoxide and carbon dioxide is 4: 8 or 1: 2.
It should be noted, however, that this law is the development of Proust's law, although it was found before Proust's own law. This law also states that atoms can not be shaped like half shards, must be integers. This law is strong because it is supported by atomic theory.
Hopefully can be understood
thanks for comment.
What is the relationship of mole to mass?
BalasHapusThe relationship between mol and mass is:
HapusQuantity (in mol) = Mass of compound or element (gram) / Molar mass of compound or element (gram / mol).
Hopefully can be understood
thanks for comment.
Please explain to me the relationship between mole and molarity???
BalasHapusThe relationship between mol and molarity is:
HapusThe molarity of the solution is obtained by dividing the mole per volume.
Hopefully can be understood
thanks for comment.
What is benefit of stoichiometry in daily life?
BalasHapusIn everyday life, the concept of stoichiometry can be found, among others:
HapusA. Charging battery
B. Capillarity Symptoms in water
C. Gas Kinetic Theory
D. Calorimeter
E. Heating / cooking water
Hopefully can be understood
thanks for comment.
Please explain to me about CONCEPT MOL!
BalasHapus
HapusThe number of particles is expressed in units of moles. The mol unit is now expressed as the number of par-tarts (atoms, molecules, or ions) in a substance. Experts agree that one mole of the substance contains the number of particles equal to the number of particles in 12.0 grams of C-12 isotope of 6.02 x 1023 particles. The number of particles is called Avogadro Numbers (NA = Number Avogadro) or in German Numbers Loschmidt (L).
What is relationship volume of gas and moles?
BalasHapusThe mole and volume relationships are divided into two in standard and non-standard state.
Hapus1.Gas on the standard state
Measurement of gas quantity depends on temperature and gas pressure. If the gas is measured in a standard state, then the volume is called the molar volume. The molar volume is the volume of 1 mole of gas measured under standard circumstances. Standard circumstances are conditions at 0 ° C (or 273 K) and atmospheric pressure (or 76 cmHg or 760 mmHg) or STP (Standard Temperature and Pressure).
The amount of gas molar volume can be determined by the ideal gas equation: PV = nRT
P = pressure = 1 atm
N = mol = 1 mole of gas
T = temperature in Kelvin = 273 K
R = gas constant = 0.082 liter atm / mol K
Then:
P V = nRT
V = 1 x 0.082 x 273
V = 22,389
V = 22.4 liters
Thus, the standard volume = VSTP = 22.4 Liter / mol.
Can be formulated: V = n x Vm
2. Gas in a non-standard state
If the gas volume is measured on the ATP (Am-bient Temperature and Pressure) or better known as non-STP then use the formula:
P V = n R T
P = pressure, the unit P is the atmosphere (atm)
V = volume, unit V is liter
N = mol, the unit n is the mole
R = gas constant = 0.082 liter atm / mol K
T = temperature, unit T is Kelvin (K)