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3 years ago

How many moles of cl- ions are needed to completely combine with 0.25 moles of mg+2 ions? 0.175 0.75 0.50 0.25 0.125?

1 answer:

6 0

When magnesium ions and chloride ions form a compound the chemical formula would be MgCl2 which means that for every 1 atom of Mg+ there would be 2 atoms of Cl- bonded. This would be proportional to units of moles.

Moles Cl- = 0.25 mol Mg2+ ( 2 mol Cl - / 1 mol Mg2+) = 0.50 mol Cl- would be needed

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Which shows the formula for an Organic acid

tresset_1 [31]

Answer:
The formula of Organic acid is as follow,

R-COOH

Explanation:
The class of organic acids is called Carboxylic Acids. In above general structure, R is alkyl group and can vary. While -COOH is the functional group.
Carboxylic Acids has the tendency to loose protons and their pKa value depends upon the alkyl group. For example the pKa value of Acetic acid (R = -CH₃) is 4.7. The driving force for this acidity is the stability of carboxylate (conjugate base) due resonance. i.e

RCOOH ⇄ RCOO⁻ + H⁺
Where;
RCOO⁻ = Carboxylate Ion (Conjugate base)

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3 years ago

Imagine a chemist is in the lab and trying to make some chemical reactions happen. In one reaction she reacts chemicals in an ex

VikaD [51]

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3 years ago

The last column of the periodic table contains the noble gases, elements that do not easily form chemical bonds. Why don’t these

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2 years ago

What is the vapor pressure of the solution if 35.0 g of water is dissolved in 100.0 g of ethyl alcohol at 25 ∘C? The vapor press

masya89 [10]

Answer: The vapor pressure of the solution is 43.55 mmHg

Explanation:

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ .....(1)

For water:

Given mass of water = 35.0 g

Molar mass of water = 18 g/mol

Putting values in equation 1, we get:

$\text{Moles of water}=\frac{35.0g}{18g/mol}=1.944mol$

For ethyl alcohol:

Given mass of ethyl alcohol = 100.0 g

Molar mass of ethyl alcohol = 46 g/mol

Putting values in equation 1, we get:

$\text{Moles of ethyl alcohol}=\frac{100.0g}{46g/mol}=2.174mol$

Total moles of solution = [1.944 = 2.174] moles = 4.118 moles

Mole fraction of a substance is given by:

$\chi_A=\frac{n_A}{n_A+n_B}$

For water:

$\chi_{\text{water}}=\frac{n_{\text{water}}}{n_{\text{water}}+n_{\text{ethyl alcohol}}}$

$\chi_{water}=\frac{1.944}{4.118}=0.472$

For ethyl alcohol:

$\chi_{\text{ethyl alcohol}}=\frac{n_{\text{ethyl alcohol}}}{n_{\text{water}}+n_{\text{ethyl alcohol}}}$

$\chi_{\text{ethyl alcohol}}=\frac{2.174}{4.118}=0.528$

Dalton's law of partial pressure states that the total pressure of the system is equal to the sum of partial pressure of each component present in it.

To calculate the vapor pressure of the solution, we use the law given by Dalton, which is:

$P_T=\sum_{i=1}^n (p_i\times \chi_i)$