Liquid
Compressibility, k
Pa-1 x 10-11
Atm-1 x 10-6
Compressibility is the fractional change in volume per unit increase in pressure. For each atmosphere increase in pressure, the volume of water would decrease 46.4 parts per million. The compressibility k is the reciprocal of the
Bulk modulus, B. (Data from Sears, Zemansky, Young, and Freedman, University Physics, 10th Ed., Section 11-6. )