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2 years ago

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I NEED HELP FAST !The density of aluminum is 2.70 g/cm3. How large a cube, in cm3, would contain 2.00 x 10^24 atoms of aluminum?

Use dimensional analysis to solve and show all work including units on every number!

1 answer:

IceJOKER [234]2 years ago

4 0

Explanation:

2.70 times 2.00 times 10...24=

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What is the mass of 2.25 x 10^25 atoms of lead

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Answer: the amount of a substance that contains 6.02 x 1023 respective particles of that

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Molar Mass: the mass of one mole of an element

CONVERSION FACTORS:

1 mole = 6.02 x 1023 atoms 1 mole = atomic mass (g)

Try:

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6.5 moles 6.02 x 1023 atoms = 3.9 x 1024 atoms

1 mole

2. How many moles of argon are in a sample containing 2.4 x 1024 atoms of argon?

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6.02 x 1023 atoms

3. How many moles are in 2.5g of lithium?

2.5 grams Li 1 mole = 0.36 mol

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4. Find the mass of 4.8moles of iron.

4.8 moles 55.8 g = 267.84 g = 270g

1 mole

MOLE PARTICLES

(ATOM)

MASS

(g)

1 mole = molar

mass

(look it up on

the PT!)

1 mole =

6.02 x 1023

atoms

1 mole = 6.02 x 1023 atoms 1 mole = atomic mass (g)

Two Step Problems:

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PRACTICE PROBLEMS:

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625g of copper 1 mol = 9.77 mol Cu

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6.02 x 1023 atoms

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1 mole

4. How many atoms are in 4.0g of potassium?

4.0 g 1 mole 6.02 x 1023 atoms = 6.2 x 1022 atoms

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Explanation:

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