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A sample of pure gas at 20°C and 670 mmHg occupied a volume of 562 cm³. How many moles of gas does this represent?

User Icex
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Final answer:

To determine the number of moles of gas represented by the given sample, use the ideal gas law equation PV = nRT.

Step-by-step explanation:

To determine the number of moles of gas represented by the given sample, we need to use the ideal gas law equation, PV = nRT, where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, and T is the temperature in Kelvin.

To convert the given temperature from Celsius to Kelvin, we use the equation K = °C + 273.15.

Given:
Temperature (T) = 20°C = 20 + 273.15 = 293.15 K
Pressure (P) = 670 mmHg
Volume (V) = 562 cm³ = 562 mL

The ideal gas law equation can be rearranged to solve for n:

n = PV / RT

Substituting the given values:

n = (670 mmHg * 562 mL) / (0.0821 L·atm/mol·K * 293.15 K)

Simplifying the equation:

n = 0.332 mol

Therefore, the given sample of gas represents 0.332 moles of gas.

User Hani Honey
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