Solution

 Solution
1.) In chemistry, a solution is a homogeneous mixture composed of only one phase. In such a mixture, a solute is a substance dissolved in another substance, known as a solvent. The solvent does the dissolving. The solution more or less takes on the characteristics of the solvent including its phase, and the solvent is commonly the major fraction of the mixture. The concentration of a solute in a solution is a measure of how much of that solute is dissolved in the solvent.

2.) Solution is a type of mixture that cannot be separated easily, such as by hand, with magnets, or with common tools. A solution contains a solute and a solvent. The solute is the substance in the mixture that will dissolve, which means that the particles become too small to be seen. A solvent is a liquid, most commonly water(the universal solvent). The solvent is the substance that actually does the dissolving. Properties of a solution may change, but some may remain the same. For example, the water may become sweet when you add sugar, but the water will remain a liquid. The statement " a solution is always clear, but not always colorless" means that the solution will be uniform, or the same throughout, but may change color as a result of dissolving.

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Differentiate Homogeneous From Heterogeneous Mixture

Differentiate Homogeneous From Heterogeneous Mixture

A homogeneous mixture is a mixture where the components that make up the mixture are uniformly distributed throughout the mixture.

Homogeneous mixtures: air, blood, saturated sugar water

A heterogeneous mixture is a mixture where the components of the mixture are not uniform or have localized regions with different properties.

Heterogeneous mixtures: rocks, oil and water, soup, pizza

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Mixture

Mixture
In chemistry, a mixture is a material system made up of two or more different substances which are mixed but are not combined chemically. A mixture refers to the physical combination of two or more substances on which the identities are retained and are mixed in the form of alloys, solutions, suspensions, and colloids.

Mixtures are the product of a mechanical blending or mixing of chemical substances like elements and compounds, without chemical bonding or other chemical change, so that each ingredient substance retains its own chemical properties and makeup.^[1] Despite that there are no chemical changes to its constituents, the physical properties of a mixture, such as its melting point, may differ from those of the components. Some mixtures can be separated into their components by physical (mechanical or thermal) means. Azeotropes can be considered as a kind of mixture which usually pose considerable difficulties regarding the separation processes required to obtain their constituents (physical or chemical processes or, even a blend of them).

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Relate Avogadro's Number & The Mole

Avogadro's Number & The Mole

Avogadro's number and the mole are very important to the understanding of atomic structure. The Mole is like a dozen. You can have a dozen guitars, a dozen roosters, or a dozen rocks. If you have 12 of anything then you would have what we call a dozen. The concept of the mole is just like the concept of a dozen. You can have a mole of anything. The number associated with a mole is Avogadro's number. Avogadro's number is 602,000,000,000,000,000,000,000 (6.02 x 10²³). A mole of marbles would spread over the surface of the earth, and produce a layer about 50 miles thick. A mole of sand, spread over the United States, would produce a layer 3 inches deep. A mole of dollars could not be spent at the rate of a billion dollars a day over a trillion years. This shows you just how big a mole is. This number is so large that it is usually only represented in scientific notation:

6.02 x 1023

avogadro's number in scientific notation

Probably the only thing you will ever have a mole of is atoms or molecules. One mole of magnesium atoms (6.02 x 10²³ magnesium atoms) weigh 24.3 grams. 6.02 x 10²³ carbon atoms weigh a total of 12.0 grams. 6.02 x 10²³ molecules of CO₂ gas only weigh a total of 44.0 grams.

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Avogadro’s Number

Avogadro's Number

Avogadro's number, a historical term closely related to the Avogadro constant. Revisions in the base set of units of the International System of Units (SI) necessitated redefinitions of the concepts of chemical quantity. Avogadro's number was defined by Perrin as the number of molecules in one gram-molecule of hydrogen. It was later redefined as the number of atoms in 12g of the isotope carbon-12. Thus, Avogadro's number is a dimensionless quantity and has the numerical value of the Avogadro constant given in base units.
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Mole

Mole

Mole is a unit of measurement used in chemistry to express amounts of a chemical substance, defined as the amount of any substance that contains as many elementary entities (e.g., atoms, molecules, ions, electrons) as there are atoms in 12 grams of pure carbon-12 (¹²C), the isotope of carbon with relative atomic mass 12. This corresponds to the Avogadro constant, which has a value of 6.02214179(30)×10²³ elementary entities of the substance. It is one of the base units in the International System of Units, and has the unit symbol mol and corresponds with the dimension symbol N. In honor of the unit, chemists often celebrate October 23 (a reference to the 10²³ part of Avogadro's number) as "Mole Day".

The mole is widely used in chemistry instead of units of mass or volume as a convenient way to express amounts of reactants or of products of chemical reactions. For example, the chemical equation 2 H₂ + O₂ → 2 H₂O implies that 2 mol of dihydrogen (H₂) and 1 mol of dioxygen (O₂) react to form 2 mol of water (H₂O). The mole may also be used to express the number of atoms, ions, or other elementary entities in a given sample of any substance. The concentration of a solution is commonly expressed by its molarity, defined as the number of moles of the dissolved substance per litre of solution.

The number of molecules in a mole (known as Avogadro's number) is defined such that the mass of one mole of a substance, expressed in grams, is exactly equal to the substance's mean molecular mass. For example, the mean molecular mass of natural water is about 18.015, so one mole of water is about 18.015 grams. Making use of this equation considerably simplifies many chemical and physical computations.

The term gram-molecule was formerly used for essentially the same concept. The term gram-atom (abbreviated gat.) has been used for a related but distinct concept, namely a quantity of a substance that contains Avogadro's number of atoms, whether isolated or combined in molecules. Thus, for example, 1 mole of MgB₂ is 1 gram-molecule of MgB₂ but 3 gram-atoms of MgB₂.

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