Answer :

The mass (kg) of 4.6 x 10²¹ molecules of NO₂ is 351 grams.

What are molecules?

Molecules are two or more joined atoms by a chemical bond. It formed a substance that can be of similar or different molecules.

Mass is calculated by multiplying the moles and molar mass of the substance.

Mass = moles x molar mass

The number of molecules of NO₂ is 4.6 x 10²¹

To calculate the number of moles from given molecules, divide the

4.6 x 10²¹ /  6.023 x 10²³ = 7.637 x  10⁴³ moles

Our moles is calculated

The molar mass is 46 g/mol

Putting the value in the equation

mole = mass/molar mass

mass = moles x molar mass

7.637 x  10⁴ x 46  = 351 grams

Thus, the mass (kg) of 4.6 x 10²¹ molecules of NO₂ is 351 grams.

To learn more about mass, refer to the link:

brainly.com/question/9909261

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