Density Flashcards
what is density
the measure of the compactness of a substance
what does density relate to
the mass of the substance and how much space it takes up
what is the formula for density
- density = mass / volume
- p = m /v
what are the two possible unit of density
g/cm^3 or kg/cm^3
what is density not affected by
the size or shape of the object
what does the average density of an object determine
- whether it floats or sinks
- a solid will float on the fluid if it has a lower average density than the fluid
how do you find the density of a substance
measure its mass and volume and use the density formula
what is the easiest way to measure the density of a liquid
by using a measuring cylinder
how do you find the density of a liquid
- use a mass balance to measure the mass of the empty cylinder
- pour the liquid and record the increase in mass (total recording - mass of cylinder)
- volume of the water is shown on the measuring cylinder (1ml = 1cm^3)
- use the density equation (mass / volume)
what would be the thinking process behind measuring the volume of an object with an irregular shape
by using the fact that an object submerged in water will displace a volume of water equal to its own volume
what is the process of measuring the density of an object with an irregular shape
- measure the mass (m1) of the object using a mass balance
- fill the bottle with a liquid of a known density
- place the stopper in the bottle and dry the outside
- measure the mass of the bottle (m2)
- empty the bottle and place the object into the density bottle
- repeat the filling and placing steps
- measure the mass of the bottle (m3) and calculate the volume of displaced water
how would you calculate the mass and volume of the displaced water in the experiment to find the density of an irregularly shaped object
- the mass of the displaced water = m2 - (m3 - m1)
- you know the density of water, so you can use volume = density / mass to find the volume displaced
- this equals the volume of the object
how do you calculate the density of the irregularly shaped object in the experiment
by calculating the density of the object using p = m / v with the mass measured in step 1 and the volume calculated in the final steps