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3 years ago

How many moles of helium are needed to fill a balloon to a volume of 5.3 L at 22 ℃ and 632 mmHg?

Chemistry

1 answer:

son4ous [18]3 years ago

6 0

Answer:

0.18 moles

Explanation:

Applying,

PV = nRT................... Equation 1

Where P = pressure, V = volume, n = number of moles, R = molar gas constant, T = temperature.

make n the subject of the equation

n = PV/RT............... Equation 2

Given: V = 5.3 L, T = 22 °C = (22+272) K = 295 K, P = 632 mmHg = (0.00131579×632) = 0.8316 atm, R = 0.083 L.atm/K.mol

Substitute these values into equation 2

n = (0.8316×5.3)/(0.083×295)

n = 0.18 moles

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3 years ago

When radium-226 (atomic number-88) decays by emitting an alpha particle it becomes _____.

topjm [15]

Answer:

d. Radon-222

Explanation:

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3 years ago

Balance the following equation:<br> K+ H2O + H2 + KOH

alex41 [277]

Answer:

2K + 2H2O → H2 + 2KOH

Explanation:

Find how many atoms you have on both sides then add 2 to both sides.

Reactant: Products:

K: 1+1=2 K: 1+1=2

H: 2+2=4 H: 3+1=4

O: 1+1=2 O: 1+1=2

Therefore it is balanced. Hope this helps

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2 years ago

A student sees an absorbance a=1.140 for his solution that has a concentration of c=1.50*10-4 m using 0.50 cm cuvette. what is t

777dan777 [17]

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The formula to be used to calculate molar extinction coefficient is -

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The given values are in required units, hence, there is no need to convert them. Directly keeping the values in formula to find the value of molar extinction coefficient.

Rewriting the formula as per molar extinction coefficient -

ξ = $\frac{A}{cl}$