How many moles are in 3.4 x 10-7 grams of silicon dioxide?

There are 5.67 × 10-⁹ moles in 3.4 x 10-7 grams of silicon dioxide.

CALCULATE MOLES:

The number of moles in a substance can be calculated by dividing the mass of the substance by its molar mass. Molar mass of silicon dioxide (SiO2) = 28 + 16(2) = 60g/molAccording to this question, there are 3.4 x 10-⁷ grams of silicon dioxide. The number of moles is calculated thus:no. of moles = 3.4 x 10-⁷ g ÷ 60g/molno. of moles = 5.67 × 10-⁹molTherefore, there are 5.67 × 10-⁹ moles in 3.4 x 10-7 grams of silicon dioxide.

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Molar mass is  28+32 = 60
So take 3.4 x 10^-7/60 and get about 5.7 x 10^-9

7is b8 is d9 is c10 is a11 is d

Yes, endothermic means it turns cold. and some chemical changes include change of tempature.