Calculate the mass of 6.900 moles of glucose, C6H12O6. Use the correct number of significant figures in your answer.

Calculate the number of boron atoms in a 50.0g sample of tetraborane B4H10.   Be sure your answer has a unit symbol if necessary, and round it to 3 significant digits.

What proportion of the mass of glucose is accounted for by oxygen? You may express your answer either as a proportion or a percentage. In either case, use 4 significant figures.

What mass of copper(I) phosphate contains 3.20×1023 oxygen atoms? Provide your answer in decimal notation, rounded to three significant figures.

How many formula units are in 30.912 g of potassium permanganate? Give answer to the correct number of significant figures.  If exponents are needed, use the format 1.23E+4.  Do not include unit or substance for this answer.

Calculate the mass of forsterite (Mg₂ SiO4) that contains a billion (1.000 × 10³) magnesium atoms. Be sure your answer has a unit symbol if necessary, and round it to 4 significant digits. 0 x10 X 3

21.1 g O2 20.5 g C8H10 Express the answers in molecules to three significant figures

4.8×1025 O3O3 molecules Express your answer using two significant figures.   Calculate the mass in grams of each sample.

Calculate the number of atoms in a 2.17 x 105 mole sample of neon. Your answer should be rounded to the correct number of significant figures and written in scientific notation.

Nicotine is an alkaloid that is derived from tobacco plants that acts as a stimulant on the human nervous system. It has the molecular formula C10H14N2. Calculate its molar mass to 3 decimal places. You do not need to include units for this particular answer, which would otherwise be g/mol.