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DENSITY. THE AMOUNT OF MATTER IN A GIVEN VOLUME. Density does not change with. A block has a length of 8 cm, A width of 4 cm, and a height of 2 cm. changes in size or shape. What does that mean?? If you cut the matter into pieces each piece will have the same density. 4 cm. 2 cm.
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DENSITY THE AMOUNT OF MATTER IN A GIVEN VOLUME.
Density does not change with A block has a length of 8 cm, A width of 4 cm, and a height of 2 cm. changes in size or shape. What does that mean?? If you cut the matter into pieces each piece will have the same density. 4 cm 2 cm 8cm Calculate density. Mass of the block is 32 grams.
4 cm Density of the block is 0.5 g/ccm What would happen if you cut that block in half? Into quarters? 2 cm 8 cm Now the length is 4 cm, height Is still 2 cm and width is still 4 cm. If we calculate the density it would Be??????? Be careful, remember If you cut the block in half, what Would happen to mass????
Density for our new block is 0.5 g/ccm. Now what would happen if we quartered the same block. Now the new dimensions are L= 2cm, W = 4 cm, and H = 2 cm. Taking into account that mass Has changed as well, calculate The new density.
In all three cases, density remained 0.5 g/ccm. This is because, both mass and volume changed Proportionately. If one changed and the other did not, then Density would have changed.
D = Mass/Volume Density of water is a standard used To compare all other matter. The density of water is: 1 gram/cubic cm
A block has a mass of 10 grams and a volume Of 15 cubic cm. Its density is 0.67 g/ccm. Any density less than water will float. The value of the density will equal The level at which the object will Float in the water.
A block has a mass of 50 grams and a volume of 25 ccm. The density is ????? Where will the Block end up???
Archimedes Density determines the buoyancy of matter. Buoyancy is determined by the amount of water displaced by the matter. The more water displaced the less buoyant the matter. Densities > 1 will sink. Matter has the ability to displace a lot of water. Densities < 1 will float. Matter will not be able to displace a lot of water.
CHEMICAL PROPERTIES • PROPERTIES THAT DETERMINE COM- • POSITION OF MATTER: elements and their • ratios found in the matter/compound. • REACTIVITY: will element/compound • react with other elements/compounds. • Iron + oxygen Iron oxide (rust)
CHEMICAL CHANGES • CHANGE CHEMICAL COMPOSITION OF • MATTER: • Iron + oxygen Iron oxide (rust) • CHANGED COMPOUND/MATTER HAS • PROPERTIES THAT ARE DIFFERENT THAN THE ORIGINAL. • CHEMICAL CHANGES ARE NOT • REVERSIBLE. Rust can not be returned • to oxygen and iron.
Chemical and physical comparison Physical properties Chemical properties Properties describe the chemical composition of the matter, such as the elements that are bonded and the specific ratio; H2O, Fe2O3. Chemical properties do not change without changing the composition of matter. Properties are not affected by size. • Properties that describe the physical appearance of matter, such as size, shape, texture, density. • Properties can change and be returned to original properties. • Properties may be size dependent or size independent.
Chemical and Physical changes Physical Changes Chemical Changes The changes affect the appearance of matter. The changes change the chemical composition of the matter. These changes cannot be reversed. The properties of the new matter are different than the original. • The changes affect the way the matter appears; size, color, shape. • These changes can be reversed. • The properties of the new matter are the same as the original.