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3 years ago

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!need actual answers 7 questions need help !!!!! take your time!! will check soon this is my homework practice please check my s

creenshot for the a,b,c and d answer choices. just a bit out of it today to do them thanks... :)
1 How many moles of Boron is 1.25 x 10²³ atoms of Boron?

2 How many moles of Al is 4.21 x 10²⁴ atoms of Al? *

3 How many moles of Ar is 2.53 x 10²⁴ atoms of Ar

4 How many moles is 2.80 x 10²⁴ atoms of Hydrogen?

5 How many atoms are in 3.69 moles of Na?

6 How many atoms are in 3.69 moles of Na?

7 How many atoms are in 8.27 x 10⁻⁶ moles of Co?

1 answer:

Artyom0805 [142]3 years ago

3 0

Answer:

1. 0.207 moles

2. 6.99 moles

3. 4.20 moles

4. 4.65 moles

5. 2.221 × 10²⁴ atoms

6. 2.221 × 10²⁴ atoms

7. 4.979 × 10^18 atoms

Explanation:

The number of moles and atoms can be calculated using the Avagadro's number, which is 6.02 × 10^23 atoms.

mole = number of atoms ÷ Avagadro's number.

1. Mole = 1.25 x 10²³ ÷ 6.02 × 10^23

mole of Boron = 0.207 × 10(23-23)

= 0.207 × 10^0

= 0.207 moles

2. Mole = 4.21 x 10²⁴ ÷ 6.02 × 10^23

mole of Aluminum = 0.699 × 10(24-23)

= 0.699 × 10^1

= 6.99 moles

3. Mole = 2.53 x 10²⁴ ÷ 6.02 × 10^23

mole of Argon = 0.420 × 10(24-23)

= 0.420 × 10^1

= 4.20moles

4. Mole = 2.80 x 10²⁴ ÷ 6.02 × 10^23

mole of Hydrogen = 0.465 × 10(24-23)

= 0.465 × 10^1

= 4.65 moles

5. Number of atoms of Na = 3.69 × 6.02 × 10²³

= 22.21 × 10²³

= 2.221 × 10²⁴ atoms

6. Number of atoms of Na = 3.69 × 6.02 × 10²³

= 22.21 × 10²³

= 2.221 × 10²⁴ atoms

7. Number of atoms of Co = 8.27 x 10⁻⁶ moles × 6.02 × 10²³ atoms

= 49.79 × 10^17

= 4.979 × 10^18 atoms

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