NEED HELP ASAP WILL GIVE BRAINLIEST
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Answer:
0.2491
Explanation:
1mole of a gas contains 6.02 × 10²³molecules
x moles will contain 3.408 × 10²¹
x = 1 × 3.408 × 10²¹/ 6.02 × 10²³
= 5.66 × 10^-3moles
Mole = mass/ molar mass
mass = Mole × molar mass
= 5.66 × 10^-3 × 44.01
= 249.0966 × 10^-3
= 0.2490966
to 4 decimal places = 0.2491