What is molar refraction in chemistry?

, is a measure of the total polarizability of a mole of a substance and is dependent on the temperature, the index of refraction, and the pressure. The molar refractivity is defined as. where is the Avogadro constant and. is the mean polarizability of a molecule.

What is the difference between surface tension and viscosity?

Surface tension can be considered as an incident that occurs in liquids due to the unbalanced intermolecular forces, whereas viscosity occurs due to forces on moving molecules. Surface tension is present in both moving and nonmoving fluids, but viscosity only appears in moving fluids.

What is mean by Parachor and surface tension?

Parachor is a quantity (related to surface tension) proposed by S. Sugden, in 1924. It is defined according to the formula: P = γ^1/4 M / (ρ_L- ρ_V) ... Since the works of Sugden, the Parachor concept is used to “correlate” the surface tension data of a variety of pure liquids and liquid mixtures.

Why Parachor is additive property?

It is defined as the molecular volume of liquid when its surface tension is unit. ... parachor is both an additive and constitutive property. Ie. the parachor of an individual compound can be expressed as a sum of : (1) Atomic Parachors which are the contributions of each of the atoms present in the molecule.

What is Parachor describe briefly the effect of temperature on surface tension?

As the temperature increases, viscosity decreases. Surface tension decreases with an increase in temperature. In general, surface tension decreases when the temperature increases because cohesive forces decrease with increased molecular thermal activity. ...

What do you mean by molar volume?

From Wikipedia, the free encyclopedia. In chemistry and related fields, the molar volume, symbol V_m, or of a substance is the volume occupied by one mole of it at a given temperature and pressure. It is equal to the molar mass (M) divided by the mass density (ρ):

What is drop weight method?

The drop weight method is an accurate yet simple technique for determining surface tension σ. It relies on dripping a liquid of density ρ at a low flow rate ˜Q from a capillary of radius R into air and measuring the combined volumes of the primary and satellite drops that are formed.

What is surface tension and what causes it?

The surface tension arises due to cohesive interactions between the molecules in the liquid. At the bulk of the liquid, the molecules have neighboring molecules on each side. ... As explained, the cohesive force between the molecules causes surface tension. The stronger the cohesive force, the stronger the surface tension.

What is surface tension in chemistry?

Surface tension is the energy, or work, required to increase the surface area of a liquid due to intermolecular forces. ... gasoline) or solutes in the liquid (e.g. surfactants like detergent), each solution exhibits differing surface tension properties.

Why drop of liquid is spherical in shape?

KnowHOW team explains: Water drops, or, for that matter, the drops of any other liquid, are spherical in shape due to a phenomenon called surface tension. In a liquid this acts on the surface of a freely falling drop to minimise its area. ... This results from the attraction between the molecules in the liquid.

What is Optical exaltation?

[′äp·tə·kəl ‚ek·səl′tā·shən] (physical chemistry) Optical anomaly in which the observed molar refraction exceeds the calculated one; most cases of optical anomaly are in this category.

Is Parachor a Colligative property?

(iv) Additive and Constitutive Properties: Additive and constitutive properties are physical properties that are dependent on the number of atoms in a molecule as well as their constitution. For example, atomic volume, parachor, and so on. The property of molar mass is additive. ... The property of molarity is colligative.

What is Parachor give which type of relation with viscosity?

Answer: An empirical constant for a liquid that relates the surface tension to the molecular volume and that may be used for a comparison of molecular volumes under conditions such that the liquids have the same surface tension and for determinations of partial structure of compounds by adding values obtained for ...

What is additive property in physical pharmacy?

Additive Property. A property that you can sum up. More of the substance = more of the property. This is derived from the sum of properties of individual atoms or functional groups within a molecule.

What is effect of surface tension on number of drops?

It is concluded that surface tension can be expected to decrease with decrease in droplet size over a wide range of circumstances. In addition, approximate figures are obtained for the rate at which such decreases may be expected. The decreases become significant for very small drops.

How do you calculate surface tension?

Measuring Surface Tension with a Balance Beam. Define the equation to solve for surface tension. In this experiment, the equation for surface tension will be determined by the equation F = 2sd. F is the force in newtons (N), s is the surface tension in (N/m), and d is the length of the needle used in the experiment.

Does higher viscosity mean higher surface tension?

If you relate the water and syrup demonstration you will see that a higher viscosity means a greater surface tension and a lower viscosity means a lower surface tension.

What is viscosity in physical chemistry?

Viscosity is a measure of a fluid's resistance to flow.

It describes the internal friction of a moving fluid. A fluidwith large viscosity resists motion because its molecular makeup gives it a lot of internal friction.

What is viscosity in liquids?

Viscosity is the resistance of a fluid (liquid or gas) to a change in shape or movement of neighbouring portions relative to one another. Viscosity denotes opposition to flow.