What is the final volume of a gas that initially occupies 2.50 l at 298 k and is subsequently heated to 334 k?

To answer this item, we are to think that the given gas behaves ideally such that the equation,
 
           PV = nRT

where P is the pressure, V is volume, n is the number of moles, R is the universal gas constant, and T is the temperature. When all things are equal aside from V and T, the equation becomes,

       V1T2 = V2T1

Substituting the known values,

     (2.5 L)(334 K) = (V2)(298 K)

The value of V is equal to 2.8 L. 

2.8 L. 

The density of water is 1 g/cm cubed and in order for the pebble to sink its density has to be greater than the density of water and in order for the twig to float its density has to be less than the density of water