Chemistry, Grade 7 Term 3.
All Hallows School, Brisbane.
Introduction:
What is chemistry?
Chemistry is a branch of science that deals with the composition,
structure, and properties of substances and with the transformations that
they undergo.
Quantitative vs Qualitative
Quantitative observations are measured, using numbers e.g. 12:47am,
30cm, 400 mL.
Qualitative observations are recorded using words e.g. the noise a bird
makes, the flavour of ice cream, colour of hair etc.
Inferring and Predicting
Based on your observations, an inference (logical explanation) and
prediction (what might happen in the future) may be made.
e.g.
Observation: My dog is barking
Inference: The possum is back.
Prediction: The barking will scare it away.
Units of Measurement (abbreviated):
Time: s, min, h
Weight: mg, g, kg, t
Distance: mm, cm, m, km
Volume of a Liquid: ml, L, ML
Temperature: ° C, K
Speed: km/h, m/s
Particles and Matter:
Matter definition: Matter is anything that takes up space and has mass.
Matter is split into 3 main groups: Solid, liquid and gas.
, The Movement of Particles in Matter
Particles are always vibrating. When you apply heat to them, you apply
energy, which makes the particles vibrate faster.
The particles in solids:
- Rigid, compact, vibrate in a fixed position.
- Held together by strong forces of attraction.
- Arranged in regular or irregular way
The particles in liquids:
- Arranged in random way
- Particles are close together, touching many of their neighbours, but
there are some gaps, but liquids cannot be compressed
- The particles of a liquid have enough energy to break free of some
of the forces of attraction between the particles. So, particles in
liquids can move around and can move over each other, allowing
liquids to flow and be poured.
The particles in gases:
- Particles are randomly arranged, widely spaced
- Enough energy to break free of forces of attraction, so move freely
- Move quickly in straight lines, colliding with each other and the walls
of their container
Therefore:
- Solid has the least energy and particle movement.
- Gases have the most energy and particle movement.
Phase changes between solids, liquids and gases
All Hallows School, Brisbane.
Introduction:
What is chemistry?
Chemistry is a branch of science that deals with the composition,
structure, and properties of substances and with the transformations that
they undergo.
Quantitative vs Qualitative
Quantitative observations are measured, using numbers e.g. 12:47am,
30cm, 400 mL.
Qualitative observations are recorded using words e.g. the noise a bird
makes, the flavour of ice cream, colour of hair etc.
Inferring and Predicting
Based on your observations, an inference (logical explanation) and
prediction (what might happen in the future) may be made.
e.g.
Observation: My dog is barking
Inference: The possum is back.
Prediction: The barking will scare it away.
Units of Measurement (abbreviated):
Time: s, min, h
Weight: mg, g, kg, t
Distance: mm, cm, m, km
Volume of a Liquid: ml, L, ML
Temperature: ° C, K
Speed: km/h, m/s
Particles and Matter:
Matter definition: Matter is anything that takes up space and has mass.
Matter is split into 3 main groups: Solid, liquid and gas.
, The Movement of Particles in Matter
Particles are always vibrating. When you apply heat to them, you apply
energy, which makes the particles vibrate faster.
The particles in solids:
- Rigid, compact, vibrate in a fixed position.
- Held together by strong forces of attraction.
- Arranged in regular or irregular way
The particles in liquids:
- Arranged in random way
- Particles are close together, touching many of their neighbours, but
there are some gaps, but liquids cannot be compressed
- The particles of a liquid have enough energy to break free of some
of the forces of attraction between the particles. So, particles in
liquids can move around and can move over each other, allowing
liquids to flow and be poured.
The particles in gases:
- Particles are randomly arranged, widely spaced
- Enough energy to break free of forces of attraction, so move freely
- Move quickly in straight lines, colliding with each other and the walls
of their container
Therefore:
- Solid has the least energy and particle movement.
- Gases have the most energy and particle movement.
Phase changes between solids, liquids and gases
