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natima [27]
2 years ago
11

What is the best definition of the enthalpy change Hr

Chemistry
1 answer:
Gre4nikov [31]2 years ago
5 0

Answer:

<em>The flow of thermal energy in a system, at constant atmospheric pressure AND at thermodynamic standard temperature and pressure.</em>

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A 57.0 mL sample of a 0.120 M potassium sulfate solution is mixed with 35.5 mL of a 0.118 M lead(II) acetate solution and the fo
Katarina [22]

Answer:

Limiting reagent = lead(II) acetate

Theoretical yield = 1.2704 g

% yield = 78.09 %

Explanation:

Considering:

Molarity=\frac{Moles\ of\ solute}{Volume\ of\ the\ solution}

Or,

Moles =Molarity \times {Volume\ of\ the\ solution}

Given :

For potassium sulfate :

Molarity = 0.120 M

Volume = 57.0 mL

The conversion of mL to L is shown below:

1 mL = 10⁻³ L

Thus, volume = 57.0×10⁻³ L

Thus, moles of potassium sulfate:

Moles=0.120 M \times {57.0\times 10^{-3}}\ moles

Moles of potassium sulfate  = 0.00684 moles

For lead(II) acetate :

Molarity = 0.118 M

Volume = 35.5 mL

The conversion of mL to L is shown below:

1 mL = 10⁻³ L

Thus, volume = 35.5×10⁻³ L

Thus, moles of lead(II) acetate :

Moles=0.118 \times {35.5\times 10^{-3}}\ moles

Moles of lead(II) acetate  = 0.004189 moles

According to the given reaction:

K_2SO_4_{(aq)}+Pb(C_2H_3O_2)_2_{(aq)}\rightarrow 2KC_2H_3O_2_{(s)}+PbSO_4_{(aq)}

1 mole of potassium sulfate react with 1 mole of lead(II) acetate

0.00684 moles potassium sulfate react with 0.00684 mole of lead(II) acetate

Moles of lead(II) acetate = 0.004189 moles

Limiting reagent is the one which is present in small amount. Thus, lead(II) acetate is limiting reagent. ( 0.004189 < 0.00684)

The formation of the product is governed by the limiting reagent. So,

1 mole of lead(II) acetate gives 1 mole of lead(II) sulfate

0.004189 mole of lead(II) acetate gives 0.004189 mole of lead(II) sulfate

Molar mass of lead(II) sulfate = 303.26 g/mol

Mass of lead(II) sulfate = Moles × Molar mass = 0.004189 × 303.26 g = 1.2704 g

Theoretical yield = 1.2704 g

Given experimental yield = 0.992 g

<u>% yield = (Experimental yield / Theoretical yield) × 100 = (0.992/1.2704 g) × 100 = 78.09 %</u>

3 0
3 years ago
Heat being transferred from a hot pan to our food while cooking is an example of... *
stellarik [79]

A.conduction  i hope it helps

6 0
2 years ago
Which of the following are chemicals?
Effectus [21]
I think it is c because food and clothing aren't technically chemicals however they do contain them so d is a possible answer but I think it is c
3 0
3 years ago
Carbonate oxidation number
Svetllana [295]

Answer:

-2

Explanation:

carbonate oxifation number is -2

6 0
2 years ago
How many atoms are equal to 1.5 moles of hellium
ANTONII [103]

Answer:

There are 1.8×1024 atoms in 1.5 mol HCl

Explanation:

6 0
2 years ago
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