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liraira [26]
2 years ago
5

What is the molal concentration of a solution made by dissolving 34.2 g of sucrose, c12h22o11 (molar mass 342.34 g/mol), in 125

g of water?
Chemistry
2 answers:
Anna007 [38]2 years ago
7 0
Molality is the number of moles of solute in 1 kg of solvent
number of moles of sucrose - mass of sucrose / molar mass
number of moles of sucrose - 34.2 g / 342.34 g/mol = 0.0999 mol
number of moles in 125 g of water - 0.0999 mol 
therefore number of moles in 1000 g - 0.0999 / 125 x 1000 = 0.799 mol/kg
molality of sucrose solution - 0.799 mol/kg
Alborosie2 years ago
6 0

Answer:

0.799 mol

Explanation:

Molality is the number of moles of solute in 1 kg of solvent

number of moles of sucrose - mass of sucrose / molar mass

therefore number of moles in 1000 g - 0.0999 / 125 x 1000 = 0.799 mol

Molality of sucrose solution - 0.799 mol

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Consider the chemical reaction: N2 3H2 yields 2NH3. If the concentration of the reactant H2 was increased from 1.0 x 10-2 M to 2
Brilliant_brown [7]

The equilibrium constant of a reaction is defined as:

"The ratio between equilibrium concentrations of products powered to their reaction quotient and  equilibrium concentration of reactants powered to thier reaction quotient".

The reaction quotient, Q, has the same algebraic expressions but use the actual concentrations of reactants.

To solve this question we need this additional information:

<em>For this reaction, K = 6.0x10⁻² and the initial concentrations of the reactants are:</em>

<em>[N₂] = 4.0M; [NH₃] = 1.0x10⁻⁴M and [H₂] = 1.0x10⁻²M</em>

<em />

Thus, for the reaction:

N₂ + 3H₂ ⇄ 2NH₃

The equilibrium constant, K, of this reaction, is defined as:

K = 6.0x10^{-2} = \frac{[NH_3]^2}{[N_2][H_2]^3}

And Q, is:

Q = \frac{[NH_3]^2}{[N_2][H_2]^3}

Where actual concentrations are:

[NH₃] = 1.0x10⁻⁴M

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Replacing:

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Learn more about chemical equililbrium in:

brainly.com/question/24301138

8 0
2 years ago
If 32.0 g of MgSO4⋅7H2O is thoroughly heated, what mass of anhydrous magnesium sulfate will remain?
Arada [10]
Find moles of MgSO4.7H2O

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6 0
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A mixture of gases A2 and B2 are introduced to a slender metal cylinder that has one end closed and the other fitted with a pist
REY [17]

Answer:

q < 0, w > 0, the sign of ΔE cannot be determined from the information given

Explanation:

Determination of sign of q

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After the completion of the reaction, temperature of the water bath is increased that means heat is released during the reaction and flows out of the system.

If heat is absorbed by the system, then q is indicated by positive sign and if heat is released by the system, then q is indicated by negative sign.

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