11.1- DENSITY Flashcards
How can we find how much more dense one substance is compared to with another?
measure mass of equal volumes of two substances
substance with greater mass in same volume more dense
What is the density of an object defined as?
its mass per unit volume
Equation for density?
density = m/v
What is the unit for density?
kgm-3
How can you measure the density of a regular solid? (2)
measure its mass using top pan balance
measure its dimensions using Vernier callipers or micrometre + calculate its volume using appropriate equation
do m/v
How can you measure the density of a liquid? (2)
measure mass of empty measuring cylinder. Pour some of the liquid into measuring cylinder + measure volume of liquid directly. Use as much liquid as possible to reduce percentage error in measurements
measure mass of cylinder + liquid to enable mass of liquid to be calculated
do m/v
How can you measure the density of an irregular solid? (3)
measure mass of object
immerse object on thread in liquid in measuring cylinder, observe increase in liquid level. this is volume of object
do m/v
What is an alloy?
solid mixture of two or more metals
Example of an alloy
brass
What is the alloy brass made of?
alloy of copper + zinc
Property of brass?
good resistance to corrosion + wear
Equation for density of alloy?
ρ = ρAVA + ρBVB / V
