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3 years ago

How do I answer and do this

Chemistry

1 answer:

Alecsey [184]3 years ago

3 0

a) When the reaction takes place a yellow precipitate will be formed.

b) The law of conservation of mass is true.

Explanation:

a) When a lead nitrate solution is mixed with a potassium chromate solution, a yellow precipitate containing lead forms according to the equation:

$Pb(NO_3)_2 (aq) + K_2CrO_4 (aq)$ → $2 KNO_3 (aq) + PbCrO_4(s).$

b) Law of conservation of mass for the given reaction is true.

From the given table we know the mass of reactants and its products.

Law of conservation of mass is a principle when a reaction takes place in a closed system, the mass of the products and reactants in the system doesn't change.

⇒The sum of the mass of the reactants = The sum of the mass of the products.

The sum of the reactants = 128.71+128.97.

= 257.68 g.

The sum of the products = 154.10+103.58.

= 257.68 g.

Thus law of conservation of mass is true for the above reaction.

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Explanation:

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Writing the information from the ICE Table in Equation form yields

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Manipulating the equation to get everything on one side yields

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