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Please help me

Post by Daze »

When organizing a laboratory, a student found several reagents without identification. The only, and valuable, information was that the reagents were divided into benches that classified them as salts, metals, acids and bases. With this information the student did some tests and the results are shown below.
Reagent A - acid 1.0 mol.L-1 Reagent B - metal
Reagent C - base 6.0 mol.L-1 Reagent D - base

Test 1. In a test tube, 1.0 ml of a solution of reagent A and 1.0 ml of a solution of barium chloride (BaCl₂) were added. From this reaction, two products were obtained, [1] and [2]. The product [1] is a finely divided white precipitate and [2] remains in solution.

Test 2. When determining reagents C and D, when the student opened the containers he found that Reagent C was very volatile and that it had a very strong and irritating smell, which was not observed for Reagent D. With these results he did the following tests: 1.0 ml of an AgNO3 solution was added to a NaCl solution (1.0 ml) and a precipitate [3] and a salt remained in solution [4]. The precipitate [3] was dissolved when 1.0 ml of reagent C was added, producing species [5] and [6]. The other base (reagent D) he reacted with metallic aluminum and observed the production of a precipitate [7] that dissolves in the presence of excess base D.

Test 3. Reagent B was added to a test tube with approximately 1.0 mL of 1.0 mol.L-1 HCl, resulting in the formation of [8] and a gas [9]. The product [8] reacts in the presence of reagent D resulting in the formation of a gelatinous precipitate [10] and a salt very soluble in water [11].

Identify all species present in tests 1, 2 and 3 with their respective chemical equations.
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Re: Please help me

Post by ChenBeier »

Same answer for head line.

Test one, what do you determine with BaCl2 normaly. [1] should be clear [2] can be several.

Test two, which base is volatile?
What does Silverion with chloride. Basic knowledge, precipitate [3].
What does the precipitate with this special base.
Aluminium and base does what. A very light gas.
The same with HCl Test 3
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