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2 years ago

A-potassiumB-leadC-ironD-magnesiumE-zinc

Chemistry

1 answer:

viktelen [127]2 years ago

6 0

The unknown substance : Lead

<h3>Further explanation</h3>

Given

Density of element

mass of unknown substance = 40 g

volume = 3.5 cm³

Required

The density of unknown substance

Solution

Density is the ratio of mass per unit volume

The unit of density can be expressed in g/cm³ or kg/m³

Density formula:

$\large {\boxed {\bold {\rho ~ = ~ \frac {m} {V}}}}$

Input the value to find the density of an unknown substance :

ρ = 40 g : 3.5 cm³

ρ = 11.43 g/cm³

If we look at the table, the substance which has a density of 11.43 is Lead

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2 years ago

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weqwewe [10]

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D) [PCl5]=0.00765M,[PCl3]=0.117M,and [Cl2]=0.0.117M

Explanation:

Based on the reaction:

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And knowing:

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<em>Where X represents the moles of PCl₅ that react, </em><em>reaction coordinate.</em>

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[X [X] / [0.125 - X] = 1.80

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3 years ago

A-potassiumB-leadC-ironD-magnesiumE-zinc​

A-potassiumB-leadC-ironD-magnesiumE-zinc