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Question
The mass of one steel screw is 4.11g. Find the mass of one mole of these steel screws. Compare this value with the mass of the Earth (5.98 × 1024kg). Which one of the two is heavier and by how many times?
Solution
Mass of 21 screw = 4.11 g
Mass of 1 mole of screws = 4.11 × 6.022 × 1023
= 2.475 × 1024 g
= 2.475 × 1021 kg
`("Mass of earth")/("Mass of 1 mole screws") = (5.98 xx 10^24"kg")/(2.475 xx 10^21 "kg")`
= 2416
It shows that mass of earth is 2416 times more than the mass of one mole of screws.
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