2. In a sample of 7.42 x 104 formula units of sodium carbonate, Na2CO3, determine: A) how many atoms of sodium? B) how many ions of carbonate, CO;?-? C) how many moles of NazCO3? D) how many grams of Na2CO3?

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A: Answer:Here:

Q: 0.0590x8.105æ10 1.8x10-3

A:

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Q: 40ml 30 20 40ml 10

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Q: the moles

A:

Q: Include all decimals #. Thank you

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A: A micromole = 10-3 mmole

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Q: What is the volume of a gas at 50.0°C and 0.80 atm, if there are 0.75 moles of the gas present?

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Mole Concept

Mole concept is a method to determine the amount of any substance that consists of some elemental particles using a grouping unit called ‘mole’. The mole concept enables one to handle the large amount of small elementary particles. The mole concept can be used in many calculations related to mole calculation, molar amount, mole ratio, and so on, which are significant in chemistry.