Which atom has the largest atomic radius?
(1) potassium (3) francium
(2) rubidium (4) cesium

Answer is: 3) francium.

The atomic radius of a chemical element is a measure of the size of its atom.

The atomic radius varies with increasing atomic number, but usually increases because of increasing of number of electrons.

Potassium (K), rubidium (Rb), ceasium (Cs) and francium (Fr) are in group 1 (the alkali metals) of the periodic tabl.

The atomic radius increases down the group of Periodic table and francium is on the bottom of the group 1 with highest atomic number.

in the given question, the partial pressure is calculated by using the ideal gas equation, that is, pv = nrt

here, p is pressure, v is volume = 25 l, n is number of moles = 0.0104 moles, r is gas constant = -0.0821 l.atm / mol.k

t is temperature = 273 k

p = nrt / v

p = (0.0104 mol × 0.0821 l.atm / mol.k × 273 k) / 25 l

= 0.0093 atm

he uptake of drugs from the intestine is often strongly influenced by diffusion. for example, consider a water-insoluble steroid for treating inflammation that is solubilized in aggregates of detergent molecules, called micelles. these micelles, aggregates of 80 soap molecules, have a molecular weight of 24,000, a diameter of 2.6 nm, and a charge of -27. the positively charge ions (counterions) in this system are na".