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3 years ago

Calculate the molarity of a solution given the following information: 10g NaOH dissolved in 500 mL of solution.

2 answers:

7 0

First you calculate the number of moles of the solution :

Molar mass Of NaOH = 40.0 g/mol

number of moles = mass solute / molar mass

n = 10 / 40.0

n = 0.25 moles of NaOH

Molarity = number of moles / volume in liters

500 mL = 500 / 1000 = 0.5 L

M = 0.25 / 0,5

M = 0.5 M

Answer C

hope this helps!

Gelneren [198K]3 years ago

4 0

M= mol/L

10g NaOH x 1 mol / 40gNaOH = 0.25 mol NaOH

500mL / 1000 = 0.5 L

0.25 mol NaOH / 0.5 L = 0.5 M

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What causes a gas to act in a non ideal manner?

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"The forces of attraction and the volume of the molecules" (as opposed to the volume of the container the gas is in).

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3 years ago

Yeast converts glucose to ethanol and carbon dioxide during a process known as anaerobic fermentation. The chemical reaction is

Korolek [52]

Answer:

102g

Explanation:

To find the mass of ethanol formed, we first need to ensure that we have a balanced chemical equation. A balanced chemical equation is where the number of atoms of each element is the same on both sides of the equation (reactants and products). This is useful as only when a chemical equation is balanced, we can understand the relationship of the amount (moles) of reactant and products, or to put it simply, their relationship with one another.

In this case, the given equation is already balanced.

$\tex{C_6H_{12}O_6} \longrightarrow 2 \ C_2H_6O + 2 \ CO_2$

From the equation, the amount of ethanol produced is twice the amount of yeast present, or the same amount of carbon dioxide produced. Do note that amount refers to the number of moles here.

Mole= Mass ÷Mr

Mass= Mole ×Mr

Method 1: using the mass of glucose

Mr of glucose

= 6(12) +12(1) +6(16)

= 180

Moles of glucose reacted

= 200 ÷180

= $\frac{10}{9}$ mol

Amount of ethanol formed: moles of glucose reacted= 2: 1

Amount of ethanol

= $2(\frac{10}{9} )$

= $\frac{20}{9}$ mol

Mass of ethanol

= $\frac{20}{9} \times[2(12)+6+16]$

= $\frac{20}{9}(46)$

= 102 g (3 s.f.)

Method 2: using mass of carbon dioxide produced

Mole of carbon dioxide produced

= 97.7 ÷[12 +2(16)]

= 97.7 ÷44

= $\frac{977}{440}$ mol

Moles of ethanol: moles of carbon dioxide= 1: 1

Moles of ethanol formed= $\frac{977}{440}$ mol

Mass of ethanol formed

= $\frac{977}{440} \times[2(12)+6+16]$

= 102 g (3 s.f.)

Thus, 102 g of ethanol are formed.

Additional:

For a similar question on mass and mole ratio, do check out the following!

brainly.com/question/1685725

8 0

1 year ago

Examine the given reaction. NH4NO3(s) → NH4+(aq) + NO3–(aq) ΔH° = 25.45 kJ/mol ΔS° = 108.7 J/mol·K Which of the given is correct

kobusy [5.1K]

Answer:

B)−6,942 J /mol

Explanation:

At constant temperature and pressure, you cand define the change in Gibbs free energy, ΔG, as:

ΔG = ΔH - TΔS

Where ΔH is enthalpy, T absolute temperature and ΔS change in entropy.

Replacing (25°C = 273 + 25 = 298K; 25.45kJ/mol = 25450J/mol):

ΔG = ΔH - TΔS

ΔG = 25450J/mol - 298K×108.7J/molK

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Right solution is:

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3 years ago

Volume increases, pressure stays the same, temperature

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Temperature decreases (?)

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3 years ago

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Answer:

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The description applied to power sources tends to match the names applied to the source of energy. Sometimes Latin, or other word derivations are used.

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