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worty [1.4K]
3 years ago
9

How many moles of magnesium chloride (mgcl2) are in 1.31 l of 0.38 m mgcl2?

Chemistry
1 answer:
Mumz [18]3 years ago
5 0
Molarity can be defined as the number of moles dissolved in 1 L of solution.
The molarity of MgCl₂ is 0.38 mol/L
In 1 L of MgCl₂ solution, amount go 0.38 moles is dissolved.
Therefore in 1.31 L of MgCl₂  - 0.38 mol /1 L x 1.31 L = 0.4978 mol rounded off  is 0.50 mol
In 1.31 L of solution, amount of 0.50 mol of MgCl₂ is present.
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It basically messes up the results

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If you use a ball point pen when doing a chromatogram, then the ink would separate as it is a mixture and run down the paper.

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3 years ago
Which of the following substances best conducts electricity in an aqueous solution? CH3OH
lapo4ka [179]

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2 years ago
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Explanation:

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We need to prepare:

An injection of 0.12 mg of epinephrine

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7 0
3 years ago
What is the length of a one-dimensional box for an electron (9.109 x 10-31 kg) with an n=1 energy of 479 kJ/mol? Give the answer
OverLord2011 [107]

Answer : The length of a one-dimensional box for an electron is 2.819\times 10^{31}\AA

Explanation :

The energy level of quantum particle in a one-dimensional box is given as:

E_n=\frac{n^2h^2}{8mL^2}

where,

E_n = 479 kJ/mol = 479000 J/mol

n = energy level = 1

h = Planck's constant = 6.626\times 10^{-34}Js

m = mass of electron = 9.109\times 10^{-31}kg

L = length of a one-dimensional box = ?

Now put all the given values in the above formula, we get:

479000J/mol=\frac{(1)^2\times (6.626\times 10^{-34}Js)^2}{8\times (9.109\times 10^{-31}kg)\times L^2}

L=2.819\times 10^{21}m

conversion used : 1m=10^{10}\AA

L=2.819\times 10^{31}\AA

Therefore, the length of a one-dimensional box for an electron is 2.819\times 10^{31}\AA

3 0
2 years ago
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