It depends on what type of graph you have. The easiest would be using a H-T diagram. Enthalpy of vaporization is the physical change from liquid to vapor. It occurs at a constant pressure and a constant temperature. As shown in the picture, 1 point is drawn on the subcooled liquid, and another point of the saturated vapor isothermal line. Now, the difference between those two points is the value for the enthalpy of vaporization of water.
Answer:
Sample 1 = liquid
Sample 2 = solid
Sample 3 = gas
Explanation:
Properties of gases:
Molecule of gases randomly move everywhere and occupy all available space.
Gases don't have definite volume and shape and take the shape and volume of container in which it present.
Their densities are very low as compared to the liquid and solids.
Gas molecules are at long distance from each other therefore by applying pressure gases can be compressed.
The very weak inter molecular forces are present between gas molecules.
Properties of Liquid:
Liquid have definite volume but don,t have definite shape.
Their densities are high as compared to the gases but low as compared to the solids.
In liquid, molecules are close to each other and have greater inter molecular forces as compared to the gas molecules.
Properties of solids:
Solids have definite volume and shape.
In solids molecules are tightly pack and very close to each other.
Their melting and boiling point are every high.
The densities of solids are also very high as compared to the liquid and gas.
There are very strong inter molecular forces are present between solid molecules.
Please include the statements
The law of conservation of mass applies to both cases, the following will explain how:
1. When 50 g of sugar undergoes a physical change, say for example dissolving or melting, the amount of sugar in the solution or melted form will also be 50 grams. This shows that the mass before and after the change was the same, in accordance to the law of conservation of mass.
2. When the magnesium strip is burned, this is a chemical reaction. The problem is that we only measure the mass of one of the substances involved in the reaction, the magnesium strip, which makes it seem like the mass has increased. Actually, during burning, the magnesium combines with oxygen in the air. This oxygen was present before the reaction, we just did not measure it. And after the reaction it is present in the form of product. Therefore, mass is still conserved.
Answer:
See explanation
Explanation:
Crystallization is a separation technique used to obtain pure crystals of a substance from an impure mixture of solid substances.
The impure solid is dissolved in an appropriate hot solvent. This hot solvent is able to effectively dissolve the solid. However, as the solution is allowed to cool, the pure solid separates out of the solution as crystals.
The solid is now filtered to obtain the pure solid. The solid is also washed and dried to remove any solvent contaminant.
