3 Observing

OBSERVING

KPLI SCIENCE MINOR LESSON NOTES BY SYLVESTER SAIMON SIMIN SMD, KTTC

WHAT? • Most basic skill in science • Essential to the development of other science process skills • We observe objects, substances or events through our five senses: sight, smell, touch, taste and hearing • To observe an object or substance is to explore all of its properties – color, texture, odor, shape, weight, volume, temperature, sound SSS, JSM, MPKS

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OBSERVING USES SENSES SMELLING

SEEING

It smells …….(odor) It smells like ……..

It looks …….(color, size, shape, measurements) It looks like ……..

OBSERVING

TASTING It tastes ……. It tastes like ……..

HEARING It sounds ……. It sounds like ……..

TOUCHING It feels …….(texture, temperature, pressure) It feels like ……..

SSS, JSM, MPKS

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TYPES OF OBSERVATIONS • QUALITATIVE OBSERVATIONS – Uses only senses to obtain information – Eg: • • • • •

SSS, JSM, MPKS

It is light green in colour. (sight) It has a pungent odor. (smell) It tastes sour. (taste) Its leaves are waxy and smooth. (touch) It makes a rustling sound when lightly rubbed. (hearing)

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TYPES OF OBSERVATIONS • QUANTITATIVE OBSERVATIONS – Observations that involve number or quantity – Include a reference to some standard unit of measure – Made with instruments such as rulers, balances, graduated cylinders give us specific and precise information. Approximation and comparisons are not as precise but are also quantitative observations. – Eg: • One leaf is 10 cm long and 6 cm wide. (metric rule) • The mass of one leaf is 5g. (balance) • The temperature of the room in which it grows is 22°C. (thermometer) • The plant’s leaves are clustered in groups of five. • This plant is larger than that plant. • Each flower is as wide as 3 paper clips placed end to end. SSS, JSM, MPKS

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OBSERVING CHANGES • In observing objects or phenomena that undergo physical or chemical changes, observations will be either qualitative or quantitative. • In describing a change it is important to include statements of observation made before, during and after the change occurs

SSS, JSM, MPKS

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ACTIVITY – BURNING CANDLE • Describe at least 7 (4 qualitative and 3 quantitative) obsevations before the change, 3 general statements about the changes as you observe them occuring, and 5 observations (4 qualitative and 1 quantitative) after the change has taken place. • Record your observations in the table below. SSS, JSM, MPKS

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WHAT I OBSERVED QUALITATIVE OBSERVATIONS Before 1. 2. 3. 4. 5.

QUANTITATIVE OBSERVATIONS 1. 2. 3.

During 1. 2. 3. After 1. 2. 3. SSS, JSM, MPKS

1.

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SELF CHECK QUALITATIVE OBSERVATIONS Before 1. Color: white 2. Slight odor 3. Undetectable taste 4. Cylindrical shape 5. One end flat, other end cone shaped 6. From cone extends a tuft of white, fuzzy, fibrous, composed of strands 7. Each strand is cylindrical and irregularly coiled

QUANTITATIVE OBSERVATIONS 1. Mass: 2 g 2. 5 cm long 3. 1 cm diameter 4. Each strand is 0.5 mm in diameter 5. Coil of strands is 1 mm in diameter 6. Coil extends 5 mm above tip of cone soft material

During 1. Fibrous strand turn black 2. Flame is elliptical in shape 3. Flame flickers in slight wind 4. Upper part of flame is bright yellow, lower part of flame is dull yellow with a blue margin 5. A puddle of liquid forms in place of the cone 6. Liquid material drips down side of candle; some solidifies on a cooler part of the candle, some drips to the table top. After 1. Color: white 2. Solid irregular in shape 3. Small portion of fibrous strands protrudes from wax 4. Exposed part of fibrous strands is black

SSS, JSM, MPKS

1. Mass: 1 g 2. Height of wax at highest point: 3 mm 3. Distance across wax at the widest point: 1.5 cm

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