PIMSO 2023 - Science - Secondary 4 - National Round Question 12

The amount of helium in a balloon is difficult to determine because it is difficult to weigh. However, it is possible by knowing some quantities. A helium balloon was found to have a volume of 6.8 L at 30 °C and 1 atm. Determine the mass of helium inside the balloon.
Use R = 0.0821 L·atm/(mol·K), M = 4 g/mol for He



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