Topic: States of Matter

Modernage Girls Campus:

Class: Grade 4 Students

Number of students: 15

Teacher: Ms. Neelum

Number of meetings: Twice a week

Students of grade 4 actively participated in this research. Research was conducted in the Chemistry lab of Modernage Public School and Girls College. They learnt the names of glass wares, chemicals and instruments and learnt how to use them. Glass wares used were china dish, beakers, flask, petri dish,flask,funnel ,glass rod,spatula,burner,spirit lamp,tripod stand and thermometer.We have selected few chemicals (Ice, iodine, Naphthalene, sodium chloride, sucrose, acetone, absolute ethanol, water, Sodium bicarbonate and vinegar) and studied their various properties like melting, freezing, boiling, evaporation and condensation. Experiments were conducted time to time.

As we know, matter exists in three States like solid, liquid and gas and all the 3 states are interlinked. Matter can change from one state to another through heating or cooling.

Solid: In solid particles are packed closely together. The force of attraction is so strong in solids. E.g. Ice, iodine, Naphthalene, sodium chloride etc. In liquid, particles are little bit far away, there is a weak force of attraction between particles E.g., water, vinegar, acetone, absolute ethanol etc. while in gas particles are far way. The force of attraction is very weak. E.g., water vapours, carbon dioxide gas etc.

Melting, freezing, evaporation, sublimation and condensation are common state changes. First of all, water was taken and then its three states were studied. Water is a universal solvent showing all three states of matter. Temperature was checked at every stage.

Results and Findings

1.Boiling:

It is the process of conversion into vapors by heating.

i. Water (H₂O): Young researchers investigated how water changes its state from solid (ice) to liquid to gas (steam) under different conditions of temperature. Water freezes at 0 ^oC and it boils at 100 ^oC Water is a universal solvent showing all the properties.

ii. Sodium chloride: NaCl was mixed with water and NaCl solution was prepared in a beaker. It was heated. Temperature was checked with the help of thermometer. The boiling point of water was raised from 100^oC to 102 ^oC.

iii. Sucrose:

Next, Sucrose common table sugar solution was prepared by adding sucrose in water. The sucrose solution was heated and temperature changed from 100 ^oC. to 110 ^oC.

iv. Absolute Ethanol: Boiling of Absolute Ethanol was done. It evaporated after reaching the temperature of 73 ^oC.

2. Condensation:

It is the process of conversion of vapors or steam into liquid state.

Water: To study the condensation of water, we put ice in a beaker and after some time the water droplets were seen on the outer surface of beaker, water droplets converts back into liquid due to lowering of temperature showing the process of condensation.

3. Freezing: Freezing is process of conversion of liquid to solid.

i. Water: Water froze when temperature reached to 0^oC. and converted into ice.

ii. Ethanol and Acetone: Ethanol and acetone were taken and placed in the freezer in two separate bottles for 2 days. After 2 days bottles were taken out it was observed that they were still in the liquid state. Minimum freezing range of freezer was  -18^oC while, Absolute Ethanol freezes at -114^oC and acetone freezes at -90.8^oC.

4. Evaporation:

It is the process of conversion of liquid into vapors or steam.

i. Water: Water as a universal solvent easily evaporated. When temperature reached to 100 ^oC.

ii. Acetone: Acetone was placed in a petri dish after 30 minutes acetone evaporated.

iii. Ethanol: Ethanol was also placed in a petri dish; it evaporated at room temperature but it took more than 3 hours to evaporate at room temperature. When placed in a beaker and heated it easily evaporated in few mins.

iv. Baking soda: Researchers created a chemical reaction by mixing baking soda with vinegar and heated the vinegar solution. Bubbling was observed. After just few minutes fizzing and gas formation was observed, showcasing a change in state and the release of carbon dioxide gas from the solution.

5. Sublimation: It is a process of conversion of solid to gas.

i. Ammonium chloride: First Ammonium chloride was taken in a China dish and heated by placing an inverted funnel over the China dish. After few minutes, white ammonia chloride converted into vapors.

ii. Iodine: Next, iodine was taken. It is a purple solid, when iodine was heated, it converted into gas.

iii. Naphthalene: Naphthalene was taken and its properties were studied. Naphthalene also converted into gas directly.

6. Melting:

It is the process of conversion of solid into liquid state by heating.

i. Ice: Ice was taken in a beaker and beaker was placed at the room temperature. After some time, ice changed into water showing the process of melting.

ii. Butter and Chocolate: Butter and chocolate were taken in separate China dishes and melting was done by heating. They easily melted from solid to liquid state. When the heat source was turned off. They again converted to solid state.