Density DENSITY n Density the ratio of the

Density

DENSITY n Density – the ratio of the mass of an object to its volume n Density = mass volume A conversion factor to remember:

n DENSITY The density of a substance is a ______________ of that substance. Therefore, density can be used to _______________.

TOOLS FOR SOLVING DENSITY PROBLEMS… n “manipulate the formula” Mass (grams) M g Density ml n D V “The Trusty Triangle” Volume (ml)

Density of Some Metal Substances n n n n Al – 2. 702 g/cm 3 Co – 8. 9 g/cm 3 Cu – 8. 93 g/cm 3 Au – 19. 32 g/cm 3 Fe – 7. 86 g/cm 3 Pb – 11. 34 g/cm 3 Mg – 1. 738 g/cm 3 n n n n Ni – 8. 9 g/cm 3 Pt – 21. 45 g/cm 3 Ag – 10. 5 g/cm 3 Sn – 7. 3 g/cm 3 Ti – 4. 5 g/cm 3 W – 19. 25 g/cm 3 Zn – 7. 14 g/cm 3

What is the density of a cylinder of an unknown metal that has a mass of 182. 5 g? D=m/v D= 182. 5 g /25 ml D= 7. 3 g/ml What substance is in the cylinder? Substance is tin!

2) Calculate the volume of this 2. 5 -kg granite brick. The density of granite is 2. 69 g/cm 3. V= m/d V= 2500 g/ 2. 69 V=932 cm 3 3) Aerogel is a silicon-based substance and the world’s lowest-density solid (0. 0019 g/cm 3). What is the mass, in grams, of this 1, 050 cm 3 sample of aerogel? M=DV M=. 0019 x 1050 M= 1. 995 or 2. 0 g

n A pure copper (Cu) penny has a mass of 3. 1 g and a volume of 3 0. 35 cm. What is the density of Cu? D=M/V 3. 1/. 35= 8. 9 g/cm 3

n The density of silver 3 g/cm. at 20°C is 10. 5 What is the volume of a 68 -kg bar of silver? V=M/D V= 68 g /10. 5 g/cm 3 V= 6. 5 cm 3

n A weather balloon is inflated to a volume of 2. 2 x 103 L with 37, 400 mg of He. What is the density 3 of He in g/cm ? D=m/v D= 374 / 220, 000 cm 3 D=. 0017 g/cm 3

Complete Poison Lab