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3 years ago

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Lead ions can be precipitated from aqueous solutions by the addition of aqueous iodide: Pb2+ (aq) + 2I− (aq) → PbI2 (s) Lead iod

ide is virtually insoluble in water so that the reaction appears to go to completion. How many milliliters of 3.550 M HI(aq) must be added to a solution containing 0.600 mol of Pb(NO3)2(aq) to completely precipitate the lead?

1 answer:

Angelina_Jolie [31]3 years ago

6 0

Answer:

338.00 mL

Explanation:

The lead ions come from the salt Pb(NO₃)₂ and the iodide from the acid HI, so the balanced reaction is:

Pb(NO₃)₂(aq) + 2HI(aq) → PbI₂(s) + 2HNO₃(aq)

So, the stoichiometry is 1 mol of Pb(NO₃)₂ to 2 moles of HI, then:

1 mol of Pb(NO₃)------------------------------------ 2 moles of HI

0.600 mol of Pb(NO₃)₂--------------------------- x

By a simple direct three rule:

x = 1.200 mol of HI

The acid has concentration equal to 3.550 mol/L, the volume (V) is the number of moles divided by the molar concentration:

V = 1.200/3.550 = 0.338 L

V = 338.00 mL

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Using tables , can be found that the heat of solution of CaCl2 at 25°C (≈24.7 °C) is q dis= -83.3 KJ/mol . And the molecular weight is

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Malonic acid, h2c3h2o4, is a diprotic acid with ka1= 1.5 x 10-3and ka2= 2.0 x 10-6. what is the concentration of the malonate an

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Explanation:

For the first equlibria;

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Now for the second equlibria;

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initial concentration of $C_{3}H_{2}O_{4}^{2-} =0$

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Let concentration change of $HC_{3}H_{2}O_{4}^{-}=-x$

Let concentration change of $C_{3}H_{2}O_{4}^{2-} =+x$

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Therefore, $C_{3}H_{2}O_{4}^{2-} =x= 1.68*10^{-4}M$

<h3>What is a malonic acid?</h3>

The chemical formula of malonic acid is CH2(COOH)2. Malonates include the ionized form of malonic acid as well as its esters and salts. For instance, the diethyl ester of malonic acid is called diethyl malonate.

Polyester and polymers both employ malonic acid as a precursor. Both the scent business and the flavoring sector utilize it. It is employed to regulate acidity. Malonic acid contributes to the production of fatty acids in people. Malonic acid has been found in a number of foods outside of the human body, including red beets, corn, scarlet beans, common beets, and cow milks, although its presence has not been defined. The group of organic substances known as dicarboxylic acids and derivatives includes malonic acid, also known as malonate or H2MALO.

To know more about malonic acid, visit:

brainly.com/question/13943912?referrer=searchResults

#SPJ4

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Answer:

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