Question

Procedure, Part 1:

Remember when using the experimental insert to place it under a clear plastic reaction surface; a sheet of plastic wrap works well. Place your samples such that they straddle the “X,” with some of the material in the drop over white paper, and some over the black “X.” This will allow you to see both pale solution colors, and small amounts of lightly colored solids.

1.Obtain a page of newspaper and tear it in half from top to bottom. Examine the torn edges with the hand lens and record your observations. Now take one half and tear it in half so the second tear is perpendicular (at a right angle) to the first tear. Examine the torn edges with a hand lens and record your observations. Note any differences in the two tears.

2.Observe a large piece of rock salt with a hand lens. Note things such as its color, its approximate size and shape, and the texture of the surface. Then use a rounded rock or other hard item to gently break the large piece into a few smaller pieces (try not to completely pulverize it). Note and record what you observe. Return any large dry pieces of rock salt to the vial. Now add several drops of water to a few very small flakes of salt. Record your observations after several minutes.

3.Place a very small sample of sand over the large “X” on your reaction surface insert. Observe the sand with a hand lens. Note things such as the color, approximate size and shape of granules, and the texture of the individual grains of sand. Are they all the same, or different? If there are differences, note the different types of sand grains that you observe within the sample. Note and record what you observe. Return most of the sand to the vial. Now add several drops of water to a few grains of sand. Record your observations after several minutes.

4.Place one drop of water and one drop of mineral oil separately on your small-scale reaction surface such that they do not tough. Observe and note any differences in the behavior of the water and oil. Again look at things like size, shape, mobility, color, and luster. Examine the drops with a hand lens. Record your results.

5.Place ½ teaspoon of baking soda over the large “X” on your reaction sheet. Observe the baking soda with the hand lens and record your observations. Add one teaspoon of vinegar to the baking soda and observe the reaction. Record your observations.

Procedure	Observation
1.torn paper	Vertical tear: Horizontal Tear:
2. Appearance of rock salt crystals	Before crushing: After crushing: Wet
3   Appearance of sand	Dry: Wet:
4.   oil and water on plastic	Oil: Water:
5.   baking soda and vinegar	Baking soda, dry: After combined:

Answer 1

Procedure Observation 1.torn paper                                                                                     Vertical tear: Hair let like appearance which differs from the bulk paper. White coloured Opaque Not lustrous Horizontal Tear: Similar appearance like above.There are no observable differences between the two. The hair lets are the strands of the polymer, cellulose out of which the paper is made. 2. Appearance of rock salt crystals                                       Before crushing: White, shiny(Lustrous), crystalline solid particles with sharp edges.They are hard solid in touch. Almost opaque The size of the individual particles differ, but the color and appearance is same. After crushing: The size of the particle reduced, but the color and physical properties remain the same. Wet After some time, the lumps of salt found to be separated Individual particles are found to be smaller in size (some part got dissolved in water). The shape of remaining particle is deformed Lustrous nature reduced or almost lost The color of the water is found to be same after adding to salt 3   Appearance of sand                                                                      Dry: The sand is hard and uniform on touch but differs very much under the microscope.That is the size, shape, and composition of the individual particles vary. There are round shaped, needle shaped and a lot of irregular shaped particles Different particles have varying colors such as black, brown, red and so on Size of individual components also differ-there are very small soil particles, big white,black, and red stones and a lot of medium sized components Some particle shows luster, but some are not lustrous. Few particles are transparent, through which the black color of 'X' could be seen. Wet: The water becomes brown colored Small particles are in constant motion through the water The bigger components appear the same as before. There is no change in size and shape of almost all big particles. The size of very small soil particles reduced, due to separation from each other. The sand is said to be a heterogeneous mixture since different components are present in it.It could be separated under a good microscope by handpicking. 4.   oil and water on plastic                                       Oil: It is a little brown colored.Not colorless. It formed a globule with perfect spherical shape through which 'X' could be seen It is more viscous, so have low tendency to flow. A little lustrous Water: Size and appearance of water is similar to oil. Colorless, completely transparent and nonlustrous. It also forms a spherical globule.It has a tendency to flow and spread in more areas The edges of the globule is flat Water is very much transparent compared to the oil.Size of 'X' is a little bigger when looked through water 5.   baking soda and vinegar Baking soda, dry: White, shiny, opaque particles with sharp edges. The size of particles differ, but shape and appearance are same. More like powder compared to rock salt. Not lustrous as rock salt. After combined: When vinegar is added, an immediate reaction occurred.The mass of baking soda is found to be increased with effervescence and the effervescence ceases after some time. Heat is found to be generated The mass of baking soda became porous due to the formation of bubbles The released gas is carbon dioxide and the reaction is The reaction is an acid-base reaction to form salt and water. Vinegar is acetic acid by composition.