Science

• How is scientific knowledge derived?

  It is derived from cycles of systematic observation, experimentation and analysis and from human imagination and creativity. Scientific knowledge is subject to change.
• what can applications of scientific knowledge cause?

  it can bring about beneficial or harmful consequences
• what is the nature of scientific knowledge?

  scientific knowledge is reliable, durable, and open to change in light of new evidence
• what to do when chemical can explode easily when heated?

  avoid tampering with or damaging the container which contain the chemical
• what to do when chemical is highly flammable?

  keep the chemical away from an open flame or flammable objects
• what to do when chemical releases oxygen easily which can cause fire and/or explosion?

  keep the chemical away form open flames
• what to do when chemical may damage parts of the body in contact?

  wear gloves and eye protection when using the chemical
• causes toxic or harmful effects to our body when breathed it, swallowed or in contact with skin

  wear eye protection and gloves when using the chemical
• causes harm to aquatic life

  replace the chemical with another chemical that doesn’t harm aquatic life. dispose of the chemical responsibly.
• Can cause damage or cancer to organs over time

  Wear appropriate protective clothing to prevent body parts from coming into contact with the chemical
• may explode when heated and can cause breathing difficulties when leaked in an enclosed space

  avoid tampering with or damaging the container which contains the chemcial
• causes irritation to the body

  Wear appropriate protective clothing to prevent body parts from coming into contact with the chemical
• what are the SI units for length, time, mass, and temperature 


  m, s, kg, K
• what is a random error

  a random error is caused due to unpredictable variations in the readings of the measuring device and can differ from he true value in either direction
• what is a systematic error?

  a systematic error is one that differs from the true value of measurement by a fixed amount and is caused due to some flaw in the experimental apparatus or flawed experimental technique
• what are the similarities between random and systematic errror?

  both cause differences between the true value and the measured value and both errors can be reduced by controlling the environment in which the measurements are taken or by regular maintenance of the instruments
• what is qualitative data?

  data that describe characteristics or qualities, such as colour, odour, or texture, or data that describe a category frequency or ratings.
• what is quantitative data?

  data that use numbers with a unit of measurement
• how is understanding the chemical composition of matter aplicable to our daily lives?

  We need to understand the various chemical composition of matter to be able to make informed choices in the materials we use or consume in everyday life
• what is an element?

  an element is the basic building block of both living and non-living matter
• What will happen when an element experiences chemical reactions?

  Nothing as an element cannot be broken down into simpler substances by chemical reactions
• is sugar an element?

  no, as it undergoes a chemical reaction upon heating and becomes a different substance
• what are metalloids?

  Metalloids display properties that are in between, or a mixture of, metal and non-metals. They

  have fair electrical conductivity and are brittle. They also have a shiny appearance like metals.
• what are the physical properties of metals?

  Metals are shiny, have high melting/boiling point, have good electrical conductivity, and good thermal conductivity
• what does malleable mean?

  materials which are malleable are able to be shaped by hammering or bending without breaking
• what does ductile mean?

  a material is ductile if it can be drawn into wires
• what does brittle mean?

  a material is brittle if it breaks easily when a force is applied
• what does sonorous mean?

  a sonorous material is able to produce a ringing sound when hit
• how are the elements in the periodic table arrranged?

  Elements are arranged by increasing proton/atomic number
• what are the characteristics of alkali metals?

  they are the most reactive metals in the periodic table, and react with water aggressively
• what are the characteristics of noble gases?

  they are the least reactive elements in the periodic table
• What are the characteristics of halogens?

  They are the most reactive non-metals
• How is a Bunsen flame produced?

  A Bunsen flame is produced during combustion when fuel mixed with oxygen is ignited and thus heat and light are emitted
• What is a parallax error?

  Occurs due to incorrect positioning of eyes while taking a reading on the measuring scale
• what are mixtures

  mixtures are matter that comprise two or more elements and/or compounds that are not chemically combined
• what is a compound

  a compound is a substance which consists of two or more elements that are chemically combined together
• how are compounds formed

  compounds are formed when elements combine via a chemical reaction
• how can we tell that a chemical reaction had taken place

  energy is exchanged with the environment when a compound is formed through a chemical reaction
• what are different about compounds from their constituent elements

  compounds have different properties from their constituent elements
• how are the elements in a compound combined

  the elements in a compound are always confined in a fixed proportion/ratio