CHAPTER 1

• The study of matter and its changes from one substance to another.

  CHEMISTRY
• The “CENTRAL SCIENCE”

  CHEMISTRY
• Largely an experimental science and a great deal of knowledge comes from laboratory research.

  CHEMISTRY
• Engineering has been referred to as an applied science.
• The various disciplines of engineering focus on the design and construction of structures, machines, apparatus, or processes to solve problems.
• Engineering requires an in-depth knowledge of the properties of materials and a broad knowledge of science and mathematics.
• Engineers use scientific principles in their designs, but they must also consider economics and safety issues as well as efficiency, reliability, and ease of construction.
• In many cases, the best choice of materials for a design may not be economically feasible and compromises must be made.
• TRUE OR FALSE

  An engineer uses the macroscopic properties of materials such as the hardness, strength, malleability, or conductivity to determine the appropriate choice of materials for a specific project. Many times, these macroscopic properties are experimentally measured.

  TRUE
• It is that type in which very low amount of heat or hydration is liberated during setting and harden- ing. Mostly it is used in massive concrete struc- tures like Dams etc

  LOW HEAT CEMENT
• These Types of Cement contains alumina in considerably larger proportions (average 40 percent) than normal cement...

  HIGH ALUMINA CEMENT
• It may also be defined as, a special type of Portland cement when used it gives a milky or snow-white appearance.

  WHITE CEMENT
• It is manufactured with such adjustments in the proportion of raw materials so that the cement produced attains maximum strength with-in 24-72


  RAPID HARDENING CEMENT
• Its quality is that it set into a stone-like mass within a period of fewer than 30 minutes.

  QUICK SETTING CEMENT
• In this types of cement, pigment (colour) is mixed with the Portland cement in a definite proportion. The Pigment is mixed in a finest powdered state

  COLOURED CEMENT
• THE SCIENTIFIC APPROACH

  1. Observation
  2. HYpothesis
  3. Experiment
  4. Data Collection/Analysis
  5. Communication
• describe properties or occurrences in ways that do not rely on numbers

  QUALITATIVE OBSERVATIONS -
• measurements, which by definition consist both a number and a unit.

  QUANTITATIVE OBSERVATIONS
• • “an educated guess”

  • A tentative explanation for the observations.

  • May not be correct, but it puts the scientist’s understanding of the system being studied.

  HYPOTHESIS
• These are systematic observations or measurements, preferably made under controlled conditions- that is, under conditions in which a single variable changes.

  EXPERIMENTS
• A properly designed and executed experiment enables a scientist to determine whether the original hypothesis is valid. In which case he can proceed to step 5.

  In other cases, experiments often demonstrate that the hypothesis is incorrect or that it must be modified thus requiring further experimentation.

  TRUE
• a verbal or mathematical description of a phenomenon that allows for general predictions.

  LAW
• A law simply says what happens, it does not address the question of why. They are unlikely to change over time unless a major experimental error is discovered.

  ex: Newton’s Law of Motion, Laws of thermodynamics

  TRUE
• • attempts to explain why nature behaves as it does. It is incomplete and imperfect, evolving with time to explain new facts as they are discovered.
  • Example: Big Bang Theory, Theory of Relativity, Theory of Evolution

  THEORY
• The scientific method is a method of investigation involving experimentation and observation to acquire new knowledge, solve problems, and answer questions. The key steps in the scientific method include the following:

  • Step 1: Make observations.
  • Step 2: Formulate a hypothesis.
  • Step 3: Test the hypothesis through experimentation.
  • Step 4: Accept or modify the hypothesis.
  • Step 5: Develop into a law and/or a theory.
• SOLID - rigid objects with definite shape

  LIQUID - less rigid than solids and are fluid (they are able to flow and assume the shape of their container)

  GAS - fluid and expand indefinitely

  PLASMA - a gas into which sufficient energy is provided to free electrons from atoms or molecules and to allow both species, ions and electrons, to coexist

  BEC - typically formed when a gas of bosons(a quantum particle which have whole number spin) at low densities is cooled to temperature very close to absolute zero
• 4th state of matter

  plasma
• Plasma is discovered by?

  Sir William Crookes
• PLASMA - first discovered by Sir William Crookes in 1879 using an assembly that is today known as a “Crookes tube". At the time, he labeled it “radiant matter” because of its luminous quality.
• PLASMA - Irving Langmuir coined the term “plasma” in 1928, he was an American chemist and physicist, who was apparently reminded of blood plasma.
• the most common phase of matter in the universe?

  PLASMA
• All the stars are made of plasma, and even the space between the stars is filled with a plasma, albeit a very sparse one.
• PLASMA exists at very high temperatures and are formed by super heating a gas.
• TRUE OR FALSE

  Similar to gases, plasmas also have no fixed shape or volume and will expand to completely fill the container.

  TRUE
• TRUE OR FALSE

  PLASMA exists at very low temperatures and are formed by super heating a gas.

  FALSE
• TRUE OR FALSE

  Plasma are also readily compressible with a density similar to the gas from which they were formed. In contrast to gases, which have very low electrical conductivities and are often used as insulators, plasmas have very high electrical conductivities.

  TRUE
• plasmas have very high electrical conductivities.
• 5 TH STATE OF MATTER?

  Bose-Einstein Condensate
• Bose-Einstein Condensate were first predicted theoretically by Satyendra Nath Bose, an Indian physicist who also discovered the subatomic particle named for him, the “boson”
• Albert Einstein saw that Bose's mathematics — later known as Bose-Einstein statistics — could be applied to atoms as well as light.