What is called change of state of matter ?

Similar Questions

Answer the following questions based on the $P$ - $T$ phase diagram of carbon dioxide:

$(a)$ At what temperature and pressure can the solid, liquid and vapour phases of $CO _{2}$ co-exist in equilibrium?

$(b)$ What is the effect of decrease of pressure on the fusion and boiling point of $CO _{2} ?$

$(c)$ What are the critical temperature and pressure for $CO _{2} ?$ What is their sıgnificance ?

$(d)$ Is $CO _{2}$ solid, liquid or gas at $(a)\;-70\,^{\circ} C$ under $1\; atm$, $( b )\;-60\,^{\circ} C$ under $10 \;atm,$ $(c)$ $15\,^{\circ} C$ under $56$ atm ?

A thermally insulted vessel contains $150\, g$ of water at $0\,^oC$. Then the air from the vessel is pumped out a adiabatically. A fraction of water turns into ice and the rest evaporates at $0\,^oC$ itself. The mass of evaporated water will be closes to ....... $g$ (Latent heat of vaporization of water $= 2.10 \times10^6\, Jkg^{-1}$ and Laten heat of Fusion of water $ = 3.36 \times10^5\,Jkg^{-1}$ )

  • [JEE MAIN 2019]

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 $p\to T$ diagram of water.

A child running a temperature of $101\,^{\circ} F$ is given an antipyrin (i.e. a medicine that lowers fever) which causes an increase in the rate of evaporation of sweat from his body. If the fever is brought down to $98\,^{\circ} F$ in $20$ minutes, what is the average rate of extra evaporation caused, by the drug (in $g/min$). Assume the evaporation mechanism to be the only way by which heat is lost. The mass of the child is $30\; kg$. The spectfic heat of human body is approximately the same as that of water, and latent heat of evaporation of water at that temperature is about $580\; cal \;g^{-1}$.

A substance of mass $m\, kg$ requires a power input of $P$ watts to remain in the molten state at its melting point. When the power is turned off, the sample completely solidifies in time $t$ sec. What is the latent heat of fusion of the substance

  • [IIT 1992]