Answer:
2.95 * 10^23 atoms
Step-by-step explanation:
The number of atoms in a mole is always equal to Avogadro's constant, which is 6.02214076×10²³ mol⁻¹.
To find the number of atoms in 0.490 moles of barium, multiply it with Avogadro's constant:
0.490 mol * 6.02214076×10²³ mol⁻¹ ≈ 2.9508 * 10^23
Convert to SigFigs (if necessary):
2.95 * 10^23