DENSITY

DENSITY Density is the amount of matter in a given space. Density is a ratio that compares how much mass is in an object

DENSITY IS USEFUL IIIIt allows you to identify substances – each substance has a specific density. IIIIt allows you to compare objects of different shapes and sizes.

DENSITY FORMULA Density = mass Volume Volume D = m V Units are usually grams/cm 3 or grams/mL – it depends on what units your problem is given in.

TRY THIS!  Juan found a gold chain at lunch. He wants to know if it is real or fake. The chain has a mass of 20 grams and a volume of 4 mL. What is the density?

SOLUTION DDDD = m/V DDDD = 20 g/ 4 mL DDDD = 5 g/mL IIIIf the density of real gold is 19.3 g/mL, is this chain real?

DENSITY OF WATER  Water has a density of 1.00 g/mL.  Objects with a higher density will SINK in water.  Objects with a lower density will FLOAT in water.

One MORE Example!  You want to find the density of your pencil. It has a mass of 10 grams and a volume of 20 mL. What is the density?  D = m/V  D = 10 g/ 20 mL  D = 0.5 g/mL  Will this object float or sink in water? Why?  It will float because the density is < 1