17) 8.4 / 20 x 100
18) 20 . 0.5150
19) 6,50% because (as you said) the law of definite proportions states that regardless of the amount, a compound is always composed of the same elements in the same proportion by mass
Here is the answer for the three of them
<span>N20 = 16 e-
</span><span>SeCl2 =20
</span><span>PBr3 = 26
Remember that t</span><span>o find the valence electrons in an atom you need to identify what group the element is in. An element in group 1A has 1 valence electron. If the element is in group 2A, then it has two valence electrons.</span>
The ratio of effusion rates for the lightest gas H₂ to the heaviest known gas UF₆ is 13.21 to 1
<h3>What is effusion?</h3>
Effusion is a process by which a gas escapes from its container through a tiny hole into evacuated space.
Rate of effusion ∝ 1/√Ц, (where Ц is molar mass)
Rate H₂ = 1/√ЦH₂
Rate UF₆ = 1/√ЦUF₆
Therefore, Rate H₂/ Rate UF₆ = √ЦH₂/√ЦUF₆
ЦH₂= 2.016 g/mol
ЦUF₆= 352.04 g/mol
Rate H₂ / Rate UF₆ = √352.04/√2.016 = 18.76/1.42
Rate H₂ / Rate UF₆ = 13.21
Therefore, H₂ is lower mass than UF₆. Thus H₂ gas will effuse 13 times more faster than UF₆ because the most probable speed of H₂ molecule is higher; therefore, more molecules escapes per unit time.
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Answer:
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Explanation:
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