During summers in India, one of the common practice to keep cool is to make ice balls of crushed ice, dip it in flavoured sugar syrup and sip it. For this a stick is inserted into crushed ice and is squeezed in the palm to make it into the ball. Equivalently in winter, in those areas where it snows, people make snow balls and throw around. Explain the formation of ball out of crushed ice or snow in the light of P - T diagram of water.

Explanation

Look at graph of `ptoT` of water. At `0^(@)C` temperature increase in pressure from 1 atm melts ice and decrease in pressure freezes ice.

When ice is deformed it melts paretically, pressure releases from small pores. Hence, water freezes and by merging small ice particles a steady ball can be formed.