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2 years ago

Solve without using a calculator. Substance ab2 is 60.0% a by mass. What is the percent a by mass for substance ab?

Chemistry

1 answer:

Orlov [11]2 years ago

5 0

The percent A by mass for substance AB =<u> 75%</u>

<h3>Further explanation</h3>

Proust states the Comparative Law that compounds are formed from elements with the same Mass Comparison, so that compounds have a fixed composition of elements

Empirical formula is the mole ratio of compounds forming elements.

From Substance AB₂ is 60.0% A by mass.

Let's say that AB₂ mass = 100 gram, then

mass A = 60 gram

mass B = 40 gram : 2 (coefficient in compound AB₂ = 2) = 20 gram

In compound AB:

Total mass = mass A + mass B

Total mass = 60 + 20 grams = 80 grams

Then the percentage of compound A = (60: 80) = 75%

<h3>Learn more</h3>

Grams of KO₂ needed to form O₂

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Keywords : percent mass, substance

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The given question is incomplete. The complete question is given here :

The equilibrium constant for the reaction is $1.1\times 10^6$ M.

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This value indicates that

A. $CN^-$ is a stronger base than $ONO^-$

B. HCN is a stronger acid than HONO

C. The conjugate base of HONO is $ONO^-$

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Explanation:

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When $K_{p}>1$ ; the reaction is product favoured.

When $K_{p};$ ; the reaction is reactant favored.

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