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).
Ph = A
Acid = C
Base = D
Litmus paper = B
Term = ?
Answer:
(1) breaking a pencil (2) rusting of iron
Explanation:
breaking a pencil does not alter the chemical properties of the pencil, it merely breaks it into 2 while the rusting of iron is changing the properties chemically because the iron is oxidizing and reacting with the water and oxygen in the atmosphere
Atomic mass W = 183.84 u.m.a
183.84 g ----------- 6.02x10²⁴ atoms
?? g ---------------- 2.1x10²⁴ atoms
2.1x10²⁴ x 183.84 / 6.02x10²⁴ =
3.860x10²⁶ / 6.02x10²⁴ = 641.30 g
hope this helps!
The mass would be the sum of the protons and neutrons. Your answer would be 218