Chemistry originated from an Arabic word al-kimiya , which means the art of transforming metals
Meaning of chemistryImportance
Scientific investigationChemical in daily lifeChemistry related careersChemistry-based industriesScientific attitudes and noble valuesScientific method
Meaning of chemistry~ Chemistry is the study of the composition, structure, properties and interactions of matter.
Important of chemistryChemical in daily life
~ All matter is chemical.~ Chemicals are used in almost every aspect of our lives.
Sodium chloride is used as table salt.Acetic acid is used as food preservatives.Barium sulphate is used in paints.
Important of chemistryChemistry related careers
Many careers rely on the knowledge of chemistry.Example :~Doctor~Pharmacist~Biochemist~Food technologist~Chemical engineer~Cosmetic Scientist~Forensic Scientist~Nutritionist
Important of chemistryChemistry-based industries
~ produce a wide range of useful products for consumers and support industries.~contribute greatly to the economy, society and the development of our country.Example :Petroleum industryPalm oil industryAgrochemical industryRubber industryPaint industry
Scientific Method
Gathering information about a phenomenon using our five senses.
Hot water turns colder when it is left at room temperature.
Making a smart guess or a tentative explanation about the phenomenon based on the observation.
The hot water turns colder because its temperature changes.Scientific method is a systematic method used to solve problems in science.
Asking a question based on the inference made.
How does the temperature of hot water change when the hot water is left ?
Making a general statement about the relationship between a manipulated variable and a responding variable to explain the question asked.
The longer the hot water is left at room temperature, the lower is the temperature.
A variable is a factor that affects the results of experiment. ~ Manipulated variable the factor that is purposely changed in an experiment. ~ Responding variable the factor that changes with the manipulated variable. ~ Controlled variable the factor that is kept constant throughout an experiment.
In the case :
Manipulated variable Time taken to cool down water.Responding variable Temperature of water.Controlled variable -- Pressure
Deciding how to manipulate the chosen variable, what to measure and how to keep the controlled variable constant.
The temperature of water is measured at intervals of 1 minute for a period of 5 minutes.The temperature of water is measured at the atmospheric pressure.
Determining the list of materials and apparatus, the exact procedure of the experiment, the method or collecting data and ways to analyse and interpret the collected data.
Material: Hot waterApparatus: Thermometer, stopwatch, cardboard, beaker.Procedure: 1. A beaker containing hot water is placed on a pieces of cardboard. 2.The initial temperature of water is recorded and the stopwatch is started. 3.The temperature of water is recorded at intervals of 1 minute for a period of 5 minutes.Results:
Time (minute)Temperature of water (C)Time (minute)Temperature of water (C)031425
Making observations or measurements and then recording them systematically.
Organising and analysing data. Calculations, graphs or charts are usually drawn to look for any relationship between the variables.
Making a statement about the outcome of the experiment and whether the hypothesis is accepted or rejected.
The temperature of hot water decreases with time. The hypothesis is accepted. Writing a report
Making an observationMaking an inferenceIdentify the problemMaking a hypothesisIdentifying the variablesControlling the variablesPlanning an experimentCollecting data Interpreting the dataMaking a conclusionWriting a report