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3 years ago

Given 2.14g of B2H6

Chemistry

1 answer:

Shkiper50 [21]3 years ago

5 0

Answer:

(A) is 0.0773 mol B2H6

Explanation:

Questions (A) and (B) are the same.

2.14 g B2H6 x (1 mol B2H6/27.668g B2H6) = 0.0773 mol B2H6 (A)

<u>27.668 is the molar mass of B2H6 calculated from the period table: </u>

(2 x 10.81) + (6 x 1.008) = 27.668

1.008 is the mass of H and 10.81 is the mass of B

(C)

0.0773 mol B2H6 x (6 mol H/ 1 mol B2H6) x (6.022 x 10^23 H atoms/1 mol H)

= 2.79 x 10^23 hydrogen atoms

Further Explanation:

For every 1 mol of B2H6, there are 6 moles of H (indicated by the subscript)

6.022 x 10^23 is Avogrado's number and it equals to 1 mol of anything

Avogrado's number can be in units of atoms, molecules, or particles

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nata0808 [166]

Answer:

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Explanation:

Step 1: Data given

Volume of the tire = 860 mL

Total pressure = 120 psi

Temperature = 26°C

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Step 2: Convert psi to atm

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Step 4: Calculate moles

PV = nRT

⇒ with P = the pressure = 8.163 atm

⇒ with V = the volume = 860 mL = 0.860 L

⇒ with n = the number of moles = TO BE DETERMINED

⇒ with R = the universal gas constant = 0.08206 L*atm/K*mol

⇒ with T = the temperature = 26 °C = 299 Kelvin

n = (8163*0.860)/(0.08206*299)

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Step 5: Calculate the mass of air in an air-filled tire.

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Mass = (0.2861 moles of gas) (28.8 g/mol)

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