Workings are in the picture! first you get moles of Fe2O3, then you get moles of Al and then you get mass of Al!
He because nitrogen and ozone is a molecule but helium is atom
Answer:
1. Molecular solids are usually excellent conductors of electric current.
Explanation:
Molecular solids are actually insulators (prevent electricity).
Moles (mol) = mass (g) / molar mass (g/mol)
Mass of cysteine = 150 mg = 150 x 10⁻³ g
Molar mass of cysteine = 121.16 g/mol
Moles of cysteine = 150 x 10⁻³ g / 121.16 g/mol
= 1.238 x 10⁻³ mol
Cysteine has chemical formula as C₃H₇NO₂<span>S.
Hence, 1 mole of </span>C₃H₇NO₂S produces 7 moles of H atoms.
Hence, moles of H atoms present in the sample = 1.238 x 10⁻³ mol x 7
= 8.666 x 10⁻³ mol
According to the Avogadro's constant 1 mole of substance has 6.022 × 10²³ particles.
Hence,
number of H atoms in the sample = 8.666 x 10⁻³ mol x 6.022 × 10²³ mol
= 5.219 x 10²¹