Here's the solution to 9(a):
- (a)
To calculate the density of the sand, we need its mass and its volume.
Step 1: Determine the mass of the water that fills the bottle.
Mass of water = (Mass of bottle + water) - (Mass of empty bottle)
Mass of water = 98g−35g=63 g
Step 2: Determine the volume of the bottle.
Assuming the density of water is 1g/cm3.
Volume of bottle = Volume of water that fills the bottle
Vbottle=DensityofwaterMassofwater=1g/cm363g=63cm3
Step 3: Determine the mass of the sand.
Mass of sand = (Mass of bottle + some sand) - (Mass of empty bottle)
Mass of sand = 65g−35g=30 g
Step 4: Determine the volume of the sand.
The line "Mass of bottle + sand + water on top of the sand = 80g" tells us the total mass when the bottle is filled with sand and then water is added to fill the remaining space.
Mass of (sand + water) in the bottle = (Mass of bottle + sand + water) - (Mass of empty bottle)
Mass of (sand + water) = 80g−35g=45 g
Now, subtract the mass of the sand (from Step 3) to find the mass of the water added on top of the sand.
Mass of water added = Mass of (sand + water) - Mass of sand
Mass of water added = 45g−30g=15 g
Using the density of water (1g/cm3), find the volume of the water added.
Volume of water added = DensityofwaterMassofwateradded=1g/cm315g=15cm3
The volume of the sand is the total volume of the bottle minus the volume of the water added.
Volume of sand = Volume of bottle - Volume of water added
Volume of sand = 63cm3−15cm3=48cm3
Step 5: Calculate the density of the sand.
Density of sand = VolumeofsandMassofsand
Densityofsand=48cm330g
Densityofsand=85g/cm3
Densityofsand=0.625g/cm3
The density of the sand is 0.625g/cm3.