Physical Chemistry: Question answers in Physical Chemistry

Choose your answer by clicking the radio button next to your choice and then press 'Submit' to get your score.

1. Calculate the radius of a spherical drop of liquid mercury of mass 0.649 g. The density of mercury is 1.36 × 10⁴ kg ^m-3.
a) 2.25 mm
b) 0.107 mm
c) 87.1 μm
d) 3.67 mm

2.Calculate the Coulombic potential energy of an electron at a distance of 52.9 pm from the nucleus of a helium atom.
a) +4.36 × 10^-18 J
b) -4.36 × 10^-18 J
c) -8.72 × 10^-18 J
d) +17.4 × 10^-18 J

3.A photoelectron has a kinetic energy of 3.588 × 10^-19 J. What is its speed?
a) 443.7 × 10³ m ^-1
b) 883.9 × 10³ m s^-1
c) 1.220 × 10⁹ m s^-1
d) 20.79 × 10³ m s^-1

 

4.A lump of gold of volume 127 mm³ has a mass of 2.45 mg. Calculate the density of gold.
a) 19.3 × 10^-6 kg m^-3
b) 19.3 × 10^-3 kg m^-3
c) 19.3 × 10³ kg m^-3
d) 19.3 × 10⁶ kg m^-3

 

5.In a barometer, pressure is determined by measuring the height of a column of liquid. Calculate the pressure, in units of Pa, at the bottom of a 347 mm high column of paraffin oil, of density 0.798 g cm^-3.
a) 2.720 Pa
b) 2720 Pa
c) 2720 kPa
d) 2720 MPa

Click here for answer