How many moles of rice grains are equal to 1.807x1024 grains of rice?

To calculate the number of moles of rice grains in 1.807 x 10²⁴ grains, we use Avogadro's number, which is approximately 6.022 x 10²³ grains per mole. Dividing the total number of grains by Avogadro's number gives us:

[ \text{Moles of rice} = \frac{1.807 \times 10^{24} \text{ grains}}{6.022 \times 10^{23} \text{ grains/mole}} \approx 3.00 \text{ moles} ]

Thus, 1.807 x 10²⁴ grains of rice is approximately 3.00 moles.