Chapter 1 : The Scientific endeavour

• The measuring instrument for time is the stopwatch
• The measuring instrument for temperature is the thermometer
• The measuring instrument for mass is an electronic balance
• the measuring instrument for length is a Digital caliper, meter ruler or ruler
• the measuring instrument for volume is a measuring cylinder or a syringe
• The SI unit for time is -> seconds
• The SI unit for temperature is -> K
• The SI unit for length is -> Meter
• The SI unit for volume is -> cubic meter
• A boiling tube is glassware used to contain chemicals for strong heating. Its transparent body allows for easy observation
• An evaporating dish is a small porcelain container with s sprout. It is commonly used to evaporate a liquid
• A test tube is glassware commonly used to hold chemicals. Its curved base allows for even heating and reduces the amount of chemicals left behind pouring them out. Its transparent body allows for easy observation
• A tripod stand in usually used with a wire gauze on it. It supports the apparatus that is being heated by a Bunsen burner
• A retort stand has a clamp that holds other apparatus
• A conical flask is glassware with a flat bottom and a conical body that tapers upwards to short vertical neck. Its narrow mouth allows a stopper or filter funnel to fit into it. Its conical body allows for easy mixing of liquids without spillage
• May cause damage to body parts in contact. You should wear gloves and eye protection when using the chemical

  
• Releases oxygen easily and aids burning. Should be kept away from open flames

  
• May cause cancer or damage to organs over time. You should wear appropriate protective clothing to prevent body parts from coming into contact with the chemical

  
• Catches fire easily. Should be kept away from open flames or flammable sources

  
• Causes toxic or harmful effects to the body when breathed in, swallowed or in contact with skin. Gloves and eye protection should be worn when handling the chemical

  
• May explode when heated, or causes breathing difficulties when leaked in an enclosed area. Should avoid tampering with or damaging the cylinder that contains the chemical.

  
• Causes irritation to eh body. Must wear appropriate protective clothing to prevent body parts from coming into contact with the chemical.

  
• Explodes easily when heated. Avoid tampering with or damaging the container that contains the chemical

  
• Causes harm to aquatic life. Replace the chemical with another chemical that does not harm aquatic life. Dispose of the chemical responsibility

  
• Different fields of science

  Physics is the study of matter, energy and forces

  Chemistry id the study of living things and their life processes

  Biology is the study of living things and their life processes
• Data :

  Qualitative data ; it data that uses our senses to gather information. Describes qualities or characteristics using words and/or drawings. It does not have any numerical values
• Data ;

  Quantitate data ; Uses both senses and instruments to gather information. Consists of numerical information that can be measured or counted
• Fair experiment

  Variables :

  Independant variables ; Change variable, the variable that does not remain the same

  Dependent variables ; measured variable that is dependent on the independent variable (CV affects MV)

  Controlled variables ; Constant variable
• Accuracy and precision

  Accuracy ; how close a reading or measurement is to the true or accepted value

  Precision ; how close readings and measurements of the same object are to each other
• Errors

  Parallax error ; An error when marking on the instrument is viewed from the wrong angle.

  E.g. ; The line of sight of the eye of the observer is not perpendicular to the marking on the rule.

  To remove the error, position the eye so that the line of sight is perpendicular to the marking on the ruler
• Errors

  Zero error ; An error occurs when an instrument gives a non0zero reading before a measurement is made or when the measured quantity should be zero

  E.g. ; An electronic balance has a zero error as it shows a reading before any object is placed on it.

  To remove the error ;

  1. Adjust the instrument to give a zero reading before measuring a quantity
  2. For digital instruments their zero error can be reset by pressing the "tare" button before measuring a quantity