Answer:
A. a magnet
Explanation:
Iron fillings could be separated from sand using a magnet
Crush the limestone... it would give more area for the acid to react
Answer:
1.64 moles O₂
Explanation:
Part A:
Remember 1 mole of particles = 6.02 x 10²³ particles
So, the question becomes, how many '6.02 x 10²³'s are there in 9.88 x 10²³ molecules of O₂?
This implies a division of given number of particles by 6.02 x 10²³ particles/mole.
∴moles O₂ = 9.88 x 10²³ molecules O₂ / 6.02 x 10²³ molecules O₂ · mole⁻¹ = 1.64 mole O₂
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Part B needs an equation (usually a combustion of a hydrocarbon).
Answer:
it is a weak acid
acid
Explanation:
formaldehyde is a weak acid (pK greater than 13),
Sled going down is in motion
Sled hitting rock is unbalanced
He flew because the of the sudden stop threw them off