LOWER FORM KBSM Science Density and Calculation

Density and calculation

1. Wooden block Float on water. Wooden block is Less dense than water Aluminum block sink in water. Aluminium block is more dense than water weight

2. 1.5 DENSITY • Arrange materials sequentially based on their density. • Predict whether the materials will float or sink according to their density. • Define the operational definition of density. • Calculate density using the formula (density = mass / volume) and water displacement method. • Explain the phenomena related to density differences in everyday life. • Innovate objects, food or beverage using the concept of density.

3. THE FORMULA OF DENSITY density is mass per unit volume of the substance Density   Unit = g/cm 3 or kg/m 3 Density of mercury = 13.6 g /cm 3 M M D V Every 1 cm3 has 13.6g of mercury.

4. EXAMPLE : A stone has a volume of 10 cm 3 and mass of 30 g. Find its density. Density = 30 g / 10cm3 = 3 g/cm3

5. EXAMPLE 2: A stone has a volume of 10 cm 3 and mass of 30 g. Find its density. Density   Density   Density 3 g/cm 3   M M D V

6. EXAMPLE 3: A stone has a volume of 100 cm 3 and its density is of 3 g/cm 3 . Find its mass. M M D V Mass density x volume   Mass 3 g/cm 3 x 100 cm 3   Mass 300 g  

7. Example 4 Density of mercury is 13.60 g/cm 3 . What is the volume of mercury if the mass of mercury is 12.5g. Volume = mass/density = 12.5 / 13.6 =0.9 cm 3

8. Example 5 What is density of an object X if its volume is 30 cm 3 with mass 45g. Density = mass /volume = 45/30 = 1.5 g/cm 3

9. Example 6 Object Y has density 12.8 g/cm 3 . What is the volume of the object if the mass is 100g. Volume = mass/density = 100 / 12.8 = 7.8cm 3

10. Example 7 An object has density of 8.90g/cm3. The mass of the object is 250g. Calculate the volume of the object. Volume= Mass Density = 250 8.90 = 28.1 cm 3

11. Example 8 Density of copper is 8.92 g/cm 3 . A block of copper has volume 100 cm 3 . Calculate the mass of the copper. Mass= density * volume = 8.92 * 100 = 892g

12. Example 9 Alice has a stone with mass 60g. The volume of the stone is 25cm 3 . What is the density of the stone? Density = Mass / volume = 60 / 25 = 2.4 g/cm 3

13. Different density of liquid. Which of the substances has the highest density? 2. Which of the substances has the lowest density? 3. State the substance has higher density than water but lower than Corn syrup.

14. 5 cm 10 cm 5 cm The mass of the cuboid is 750 g. Calculate the density of the cuboid. Volume of cuboid = 10 *5*5= 250cm 3 Density = mass / volume = 750 / 250 = 3 g/cm 3

15. Wood is less dense than / has lower density than the water.

16. Daniel wanted to know the density of a stone. The mass of the stone is 65g. Name the method used to determine the volume of stone. State the volume of the stone. Calculate the density of the stone. 1. Water displacement method 2. 180 ml – 150ml = 30ml= 30 cm 3 * 1 ml = 1cm 3 3. Density = mass/volume = 65 g / 30 cm 3 = 2.17 g/cm 3

17. Based on the diagram, which object has higher density than water? Explain your answer. (2m) Marble (1m) It sinks in the water (1m) candle marble

18. MATERIAL DENSITY (g/cm 3 ) Gold 19.30 Lead 11.30 Copper 8.92 Aluminium 2.70 Ice 0.92 Cork 0.24 Mercury 13.60 Seawater 1.03 Pure water 1.00 Petrol 0.80

19. Material Density Gold 19.30 Lead 11.30 Copper 8.92 LEAD COPPER GOLD Arrange the density in ascending order.

20. Compare the density of tap water and salt water. (1m) Salt water has higher density than tap water.

21. A plasticine with 50g in ball-shaped is sink in the water. Kim Wing make the same plasticine into bowl-shaped. He observed that the plasticine in bowl-shaped float on water. Explain why. (3m)

22. Plasticine in ball-shaped has higher density than the bowl-shaped. Bowl-shaped plasticine has lesser density than ball-shaped because it has larger volume than the ball-shaped. The density of bowl-shaped decreases when the volume is increase. Density  

23. Density  

24. Gold

25. Mercury Gold

26. Mercury Lead Gold

27. Mercury Lead Copper Gold

28. Mercury Lead Copper Aluminium Gold

29. Seawater Mercury Lead Copper Aluminium Gold

30. Seawater Mercury Lead Copper Aluminium Pure water Gold

31. Seawater Mercury Lead Copper Aluminium Ice Pure water Gold

32. Seawater Mercury Lead Copper Aluminium Ice Pure water Gold Petrol

33. Seawater Mercury Lead Copper Aluminium Ice Pure water Gold Petrol Cork