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4 years ago

What is the total mass of a mixture of 3.50x10^22 formula units na2so4, 0.500 mol h2o, and 7.23 g agcl?

1 answer:

5 0

Answer is: mass of the mixture is 24,47 g.
1) N(Na₂SO₄) = 3,5·10²².
n(Na₂SO₄) = 3,5·10²² ÷ 6·10²³ 1/mol.
n(Na₂SO₄) = 0,058 mol.
m(Na₂SO₄) = 0,058 mol · 142 g/mol.
m(Na₂SO₄) = 8,24 g.
2) n(H₂O) = 0,500 mol.
m(H₂O) = 0,5 mol · 18 g/mol.
m(H₂O) = 9 g.
3) m(total) = 8,24 g + 9 g + 7,23 g.
m(total) = 24,47 g.
n - amount of substance.

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Gnom [1K]

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Explanation:

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Required

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$1.77 * 10^{-2} = \frac{x^2}{0.298 - x}$

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Rewrite as:

$100x^2 + 1.77x - 0.52746 =0$

Using quadratic formula:

$x = \frac{-b \± \sqrt{b^2 - 4ac}}{2a}$

Where:

$a = 100; b = 1.77; c = -0.52746$

So, we have:

$x = \frac{-1.77 \± \sqrt{1.77^2 - 4*100*- 0.52746 }}{2*100}$

$x = \frac{-1.77 \± \sqrt{214.1169}}{2*100}$

$x = \frac{-1.77 \± 14.63}{200}$

Split

$x = \frac{-1.77 + 14.63}{200}\ or\ x = \frac{-1.77 - 14.63}{200}$

$x = \frac{12.86}{200}\ or\ x = \frac{-16.40}{200}$

$x = 0.0643\ or\ x = -0.082$

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3 years ago

During a class demonstration the potassium exploded. Suggest what might have caused this to happen

tatiyna

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3 years ago

A beaker contains 42.0 mL of carbon tetrachloride ( CCl4 , density is 1.59 g/mL). Determine how many molecules of carbon tetrach

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Answer:

Number of molecules = 2.61 x 10²³

Explanation:

Given:

Volume of tetra-chloride = 42 ml

Density = 1.59 g/ml

Find:

Number of molecules

Computation:

Mass = Volume of tetra-chloride x Density

Mass = 42 x 1.59

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0.4337 mole = 0.4337 x Avogadro number

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3 years ago

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Kitty [74]

<u>Answer:</u> The temperature of the system will be 1622 K

<u>Explanation:</u>

The equation relating the pre-exponential factor and activation energy follows:

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where,

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Putting values in above equation, we get:

$\log (2.7\times 10^{-14})=\log (1.7\times 10^{-5})-\frac{273,300}{2.303\times 8.314\times T}\\\\T=1622K$

Hence, the temperature of the system will be 1622 K

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