PLZ HELP I NEED THE ANSWERS NOW FOR A TEST
1. There are ______ moles in 9.01 x 10^23 atoms.




none of the above




15




0.150




1.50



2. How many sulfur atoms are present in 41.8 moles of sulfur?



Question 2 options:



2.52 x 10^25 S atoms




6.94 x 10^29 S atoms




1.44 x 10^24 S atoms




4.18 x 10^25 S atoms



3.How many moles would 1.00 x 10^23 molecules of methane (CH4) represent?



Question 3 options:



1.66 moles




0.166 moles




0.0166 moles




none of the above



4.How many moles of iron (Fe) are in a sample of 7.91 x 10^23 atoms of iron?



Question 4 options:



1.31 mol Fe




0.761 mol Fe




7.91 mol Fe




47.6 mol Fe



5.How many oxygen atoms are present in 2.28 moles of nitric acid, HNO3?



Question 5 options:



7.39 x 10^23 O atoms




4.119 x 10^23 O atoms




4.12 x 10^24 O atoms




1.37 x 10^24 O atoms

Respuesta :

Answer:

1. 1.50 moles

2. 2.52x10²⁵ S atoms

3. 0.166 moles

4. 1.31 moles of Fe

5. 4.12x10²⁴ atoms of O

Explanation:

1 mole is defined as the amount of atoms of ¹²C presents in 12g. This number is 6.022x10²³. That means:

1 mole of atoms = 6.022x10²³ atoms

1 mole of electrons = 6.022x10²³ electrons

1 mole of molecules = 6.022x10²³ molecules

1. Using this conversion factor, 9.01x10²³ atoms are:

9.01x10²³ atoms * (1mol / 6.022x10²³ atoms) = 1.50 moles

2. 41.8 atoms of S are:

41.8 moles * (6.022x10²³ atoms / 1mol) = 2.52x10²⁵ S atoms

3. 1.00x10²³ molecules of methane are:

1.00x10²³ molecules * (1mol / 6.022x10²³ molecules) = 0.166 moles

4. 7.91x10²³ atoms of Fe are:

7.91x10²³ atoms * (1mol / 6.022x10²³ atoms) = 1.31 moles of Fe

5. In 1 mole of HNO3 you have 3 moles of O, in 2.28 moles are:

2.28 mol * 3 = 6.84 moles of O. Atoms are:

6.84 moles of O * (6.022x10²³ atoms / 1mol) = 4.12x10²⁴ atoms of O