Question

У трьох склянках без етикеток мiстяться концентрованi рощчини кислот : сульфатноï, нiтратноï та хлоридноï. Запропонуйте спосiб розпiзнавання кислот за допомогою одного реактиву . Наведiть рiвняння вiдповiдних реакцiй . Зазначте ïх зовнiшнi ефекти.

Answer 1

Cu + 2H₂SO₄ = CuSO₄ + SO₂↑ + 2H₂O
ефекти: розчинення міді, утворення голубого розчину

Cu + 4HNO₃ = Cu(NO₃)₂ + 2NO₂↑ + 2H₂O
ефекти: розчинення міді, утворення голубого розчину, утворення бурого газу

Cu + HCl ≠

Answer 2

Identification of Acids in Unlabeled Bottles

To identify the acids in the three unlabeled bottles, you can use a single reagent called litmus paper. Litmus paper is a commonly used indicator that changes color in the presence of acids or bases. By observing the color change of the litmus paper, you can determine the nature of the substances in the bottles.

Litmus paper is usually blue in its basic form and red in its acidic form. When exposed to an acid, the litmus paper will turn red, indicating the presence of an acid. The specific color change may vary depending on the type of litmus paper used.

Here are the reactions and their corresponding equations for the three acids commonly found in the bottles:

1. Sulfuric Acid (H2SO4): - Reaction: H2SO4 + 2H2O → 2H3O+ + SO4^2- - External Effect: The litmus paper will turn red when it comes into contact with sulfuric acid.

2. Nitric Acid (HNO3): - Reaction: HNO3 + H2O → H3O+ + NO3^- - External Effect: The litmus paper will turn red when it comes into contact with nitric acid.

3. Hydrochloric Acid (HCl): - Reaction: HCl + H2O → H3O+ + Cl^- - External Effect: The litmus paper will turn red when it comes into contact with hydrochloric acid.

By using litmus paper and observing the color change, you can identify the acids in the three unlabeled bottles.