!need actual answers 7 questions need help will check soon this is my homework practice please check my screenshot 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. 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

periodic trends is an atom that gets larger as the number of electronic shells increase, the radius of atoms increases as you go down a certain group in the periodic table of elements. in general, the size of an atom will decrease as you move from left to right of a certain period.

c is having 4 valence electrons and is bonded to three hydrogens and one sulphur atom, therefore, the number of bond pair is equal to four. as all the valence electrons are used in forming the bonds so, there is no lone pair left on carbon.

s is having 6 valence electrons and is bonded to one other sulfur atom and one carbon atom, therefore, the number of bond pair is equal to 2. as only two valence electrons are used in forming the bonds so, four electrons are left. therefore, two lone pairs are present on s.