Hematite Cross
Please help!!! need to understand this for test. 10 points to best answer!! ?
Please help!!! need to understand this for test. 10 points to best answer!! ?
1.Hematite (iron ore) weighing 70.7 g was placed in a flask whose volume was 53.2mL. The flask with hematite was then carefully filled with water and weighed. The hematite and water weighed 109.3g. The
density of the water was 0.977 g/cm^3. What was the density of the hematite???
1. A cylinder with circular cross section has a radius of 2.56cm and a height of 56.32 cm. What is the volume of the cylinder?
Express the answer to correct number of significant figures.
2. If the density of silver is 10.5gm/mL, what is the mass of 1 cubic ft?
Please explain, show work and give answer. Thankss
Volume of water = 53.2 mL
Density of water = 0.977 g/cm^3 or 0.977 g/mL
Therefore weight of water = 53.2 * 0.977 = 51.9764 g
Weight of water + hematite = 109.3 g
Measured weight of only hematite = 109.3 – 51.9764 = 57.3236 g
Weight of hematite in air = 70.7 g
Loss of weight after putting in water = 70.7 – 57.3236 = 13.3764 g
Weight of displaced water = 13.3764 g
Volume of displaced water = weight of displaced water/density of water
= 13.3764/0.977 = 13.69 mL
Hematite is fully inside water.
Therefore volume of hematite = volume of displaced water = 13.69 mL
Density of hematite = mass of hematite/volume of hematite
= 70.7/13.69 = 5.16 g/cm^3
Ans: 5.16 g/cm^3
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Radius r = 2.56 cm
Height h = 56.32 cm
Volume V = PI * r^2 * h
= 1160 cm^3
Ans: 1160 cm^3
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1 ft = 12 inch = 12 * 2.54 cm = 30.48 cm
Volume = 1 cubic ft = 1 * (30.48)^3 cm^3 = 28316.85 cm^3 = 28316.85 mL
Mass = volume * density
= 28316.85 * 10.5
= 297326.925 g
= 297000 g (rounded to 3 significant figures)
Ans: 297000 g
Note that cm^3 is the same as mL
The Gothsicles – One Second Ghost
