How many atoms in 8.9 moles of iron

Acompound contains c, h, and o atoms. when 1.130 g of the compound is burned in oxygen, 1.064 g co2 and 0.3631 g h2o are produced. what is the empirical formula of this compound?

How many moles are in 7.2 x 10^23 carbon molecules? (*round to the nearest hundredth and include the unit "mol c" after your number) question 6 options:

Scientists often have to deal with numbers that are either very large or very small. for example, the radius of the sun is approximately 696,000 kilometers, while bacterial cells are as small as 1.9 × 10-4 millimeters. express each number in an alternate form.