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2 years ago

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What is the molarity of a solution made by dissolving 21.2 g of sodium hydroxide (NaOH) in enough water to make 7.92 L of soluti

on?
Molar Mass Na: 22.99 g/mol
Molar Mass O: 16.00 g/mol
Molar Mass H: 1.008 g/mol

2 answers:

g100num [7]2 years ago

6 0

M = mol/L so add all molar masses together then divide 21.2g/(molar mass) then divide by Litres

Triss [41]2 years ago

5 0

Hey there!

Attached resolution .

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What Group is this element in? (Urgent plz help)

Zepler [3.9K]

Since this is Argon it would be a noble gas

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2 years ago

A volume of 129 mL of hydrogen is collected over water. The water level in the collecting vessel is the same as the outside leve

mixas84 [53]

Explanation:

As it is given that water level is same as outside which means that theoretically, P = 756.0 torr.

So, using ideal gas equation we will calculate the number of moles as follows.

PV = nRT

or, n = $\frac{PV}{RT}$

= $\frac{\frac{756}{760}atm \times 0.129 L}{0.0821 Latm/mol K \times 298 K}$

= 0.0052 mol

Also, No. of moles = $\frac{mass}{\text{molar mass}}$

0.0052 mol = $\frac{mass}{2 g/mol}$

mass = 0.0104 g

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$P_{\text{water vapor}}$ = 24 mm Hg

= $\frac{24}{760}$ atm

= 0.03158 atm

Now, P = $\frac{756}{760} - 0.03158$

= 0.963 atm

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So, mass of $H_{2}$ = 0.0056 mol × 2

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Therefore, calculate the percentage yield as follows.

Percent yield = $\frac{\text{Actual yield}}{\text{Theoretical yield}} \times 100$

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2 years ago

Calculate the osmotic pressure of a solution containing 24.6g of glycerin in 250ml of solution at 298K

gavmur [86]

The formula to calculate osmotic pressure is
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T = Temperature in Kelvin

So,
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2 years ago

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Sliva [168]

Answer : The time passed in years is $2.83\times 10^3\text{ years}$

Explanation :

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where,

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Therefore, the time passed in years is $2.83\times 10^3\text{ years}$

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2 years ago

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Snowcat [4.5K]

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11 months ago