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3 years ago

2. Calculate the new molanty of a solution formed when 20 ml of water is added to 100 ml of

Chemistry

1 answer:

GrogVix [38]3 years ago

4 0

Answer:

New molarity = M₂ = 0.167 M

Explanation:

Given data:

New molarity = M₂ = ?

Final volume = V₂ = 100mL + 20 mL = 120 mL

Initial volume =M₁ = 100 mL

Initial molarity =V₁ = 0.2 M

Solution:

M₁V₁ = M₂V₂

0.2 M × 100 mL = M₂ × 100 mL

M₂ = 0.2 M × 100 mL/120 mL

M₂ = 20 M.mL/120 mL

M₂ = 0.167 M

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Answer:

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Explanation:

Step 1: Data given

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Pressure of methane = 732 torr

Temperature = 25.0 °C = 298 K

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

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

⇒with T = the temperature = 298 K

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⇒with V = the volume of methane = 22.0 L

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

⇒with T = the temperature = 398 K

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% yield = (actual yield / theoretical yield) * 100 %

% yield = ( 26.0 L / 41.9 L) *100 %

% yield = 62.05 %

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