Question

*************100 POINTS**************

Answer 1

1. A

2. B

3. A

4. D

5. A

Explanation:

I think that should be correct

Basically what we are trying to do here is see if we are going from molecules to moles or moles to molecules.

We know that avogadro's number is 6.022x10^23 molecules in 1 mol of anything.

So if the questions asks you to convert moles to molecules just multiply it by avogadro's number

If the question asks you to convert molecules to moles just divide by avogadro's number

Answer 2

Answer:

1) 1.0 *10^-16 moles

2) 2.2 moles

3) 4.9 * 10^25 molecules

4) 2.47 *10^24  atoms

5) 2.2 *10^23 molecules

Explanation:

How many moles of Ne contain 61,000,000 atoms?

1 mol contains 6.022 * 10^23 atoms OR 6.022 *10^23 atoms = 1 mol

6.1 * 10^7 atoms = (1/ 6.022*10^23) * 6.1 * 10^7 = 1.0 *10^-16 moles

How many moles of water contain 1.3 x 10^24 molecules?

1 mol contains 6.022 * 10^23 molecules

(1/6.022*10^23)*1.3*10^24 = 2.2 moles

How many molecules of SF6 are in 81 moles?

1 mol contains 6.022 *10^23 molecules

81 moles contain 81 * 6.022*10^23 = 4.9 * 10^25 molecules

How many atoms of carbon are present in 4.10 moles?

1 mol contains 6.022 * 10^23 molecules

4.10 moles contain 4.10 * 6.022*10^23 = 2.47 *10^24  atoms

How many molecules of NO2 are in 0.36 moles?

1 mol contains 6.022*10^23 molecules

0.36 moles contain 0.36 * 6.022*10^23 = 2.2 *10^23 molecules