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Be sure to answer all parts.

How many moles of pentane (C5H12) are contained in the following number of molecules? The answer should be provided in scientific notation.

a. 3.65 × 1023 molecules

× 10
(select)
mol

b. 2.62 × 1020 molecules

× 10
(select)
mol

Be sure to answer all parts. How many moles of pentane (C5H12) are contained in the-example-1
User Molina
by
4.8k points

1 Answer

7 votes

Answer:

a.) 6.06 x 10⁻¹ mol

b.) 4.35 x 10⁻⁴ mol

Step-by-step explanation:

To find the final answer, you need to use Avogadro's number to convert between molecules and moles. Remember to arrange the ratio/conversion in a way that allows for the cancellation of units. The answer should have 3 sig figs because the given values also have 3 sig figs.

Avogadro's Number:

6.022 x 10²³ molecules = 1 mole

a.)

3.65 x 10²³ molecules 1 mole
--------------------------------- x ------------------------------------ = 6.06 x 10⁻¹ mol
6.022 x 10²³ molecules

b.)

2.62 x 10²⁰ molecules 1 mole
-------------------------------- x --------------------------------------- = 4.35 x 10⁻⁴ mol
6.022 x 10²³ molecules

User Gatschet
by
4.5k points