Density of a Mixture of Substances
When two liquids of mass m1 and m2 having density p1 and p2 are mixed together then density of mixture is p = m1 + m2 /( m1 / p1) +( m2 + p2)
= p1p2( m1 + m2) /( m1p2 + m2p1)
When two liquids of same mass m but of different densities p1 and p2 are mixed together then density of mixture is
p = 2p1p2 / p1 + p2
When two liquids of same volume V but of different densities p1 and p2 are mixed together then density of mixture is
p = p1 + p2 / 2 Density of a liquid varies with pressure p = po [ 1 + Δp / K ]
where, po = initial density of the liquid, K = bulk modulus of elasticity of the liquid and Δp = change in pressure
Viscosity
The property of a fluid by virtue of which an internal frictional force acts between its different layers which opposes their relative motion is called viscosity.
These internal frictional force is called viscous force.
Viscous forces are intermolecular forces acting between the molecules of different layers of liquid moving with different velocities.