Science Form 2: Solubility

8.

(a)

A student found that fine sugar dissolve faster in the water. Seorang pelajar mendapati gula halus larut lebih cepat dalam air.

Diagram/ rajah 8.1 i.

Based on the observation in diagram 8.1, state the difference in the rate of dissolving of sugar. Berdasarkan pemerhatian dalam rajah 8.1, nyatakan perbezaan kadar keterlarutan bagi gula. _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ [1 mark/markah]

ii.

What inference can be made based on diagram 8.1? Apakah inferen yang boleh dibuat berdasarkan rajah 8.1? ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ [1 mark/markah]

iii.

State the hypothesis based on your observation in diagram 8.1. Nyatakan hipotesis anda berdasarkan pemerhatian dalam rajah 8.1. ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ [1 mark/markah]

8(a)

3

(b)

A student carries out an experiment to study how the size of solute affects the rate of dissolving of sugar. Time taken for sugar to dissolve completely is shown in figure 8.2. Seorang pelajar menjalankan eksperimen untuk mengkaji bagaimana saiz gula memberi kesan ke atas kadar keterlarutan gula. Masa yang diambil untuk gula melarut sepenuhnya ditunjukkan pada rajah 8.2

Beaker/ bikar A

Beaker/bikar B

Beaker/bikar C Diagram/ rajah 8.2 Based on diagram 8.2, recording the time taken in the Table 8.3. Berdasarkan Rajah 8.2 catatkan masa yang diambil dalam Jadual 8.3

Beaker bikar

Size of sugar Saiz gula

A

Large/ Kasar Medium/Sederhan

B C Jadual 8.3

a fine/ halus

Time taken for the sugar to dissolve completely. Masa yang diambil untuk gula melarut sepenuhnya. (s) 42

Table 8.3 / [ 2marks/ markah]

8(b)

2

(c)

Based on table 8.3, draw a bar chart to show the time taken to sugar dissolve completely. Berdasarkan jadual 8.3, lukiskan carta bar untuk menunjukkan masa yang diambil untuk gula melarut sepenuhnya.

8(c) [ 2marks/ markah] (d)

2

Based on the bar chart in (c), what can be said about the time taken to sugar dissolve completely. Berdasarkan carta bar di (c), apa yang boleh dikatakan tentang masa yang diambil untuk gula larut sepenuhnya. ____________________________________________________________________________ ____________________________________________________________________________ ____________________________________________________________________________

8(d)

[1 mark/markah] (e)

1

State the variables in the experiment. Nyatakan pembolehubah-pembolehubah dalam eksperimen ini. Manipulated variable Pembolehubah dimanipulasi Responding variable Pembolehubah bergerak balas Controlled variable Pembolehubah dimalarkan

(f)

Rate of stirring, volume of water, mass of sugar. Kadar pengacauan, isipadu air, jisim gula. [ 2marks/markah]

Based on the experiment, state the relationship between the rate of dissolving of sugar

8(e)

2

and size of sugar. Berdasarkan eksperimen, nyatakan hubungan antara kadar keterlarutan gula dan saiz gula. ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________

8(f)

[1 mark/markah] (g)

Based on table 8.3 and bar chart in (c), what can you deduce about the meaning of “rate of dissolving” Berdasarkan Jadual 8.3 dan carta bar di (c), apa yang boleh anda deduksi tentang maksud “kadar keterlarutan” ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ [1 mark/markah]

1

8(g)

JUMLAH

1

12

END OF QUESTIONS SOALAN TAMAT