What is the atomic fraction of zinc in aluminum for a two-component alloy containing 10 wt.% zinc? atomic weight for zinc is 65.39 g/mol and that of aluminum is 26.9 g/mol. (a)?

Answer : The correct answer for atomic fraction of Zn is 4.37

Following are the steps to find atomic fraction of Zinc in Zn-Al alloy :

Step 1 : Find mass of Zn in alloy .

Given : wt%( weight % ) of Zn = 10%

Lets assume complete mass of alloy is 100g ,so the mass of Zn =>

Multiplying both side by 100 g

Mass of Zn = 10 g

Step 2: To find mass of Al.

Mass of alloy = (mass of Al + mass of Zn )

100 g = Mass of Al + 10 g

Mass of Al = 90 g

Step 3 : To find moles of both Al and Zn

Given : Mass of Zn = 10 g Molar mass of Zn = 65.39 g/mol

Mole of Zn = 0.153 mol

Given : Mass of Al = 90 g Molar mass of Al = 26.9 g/mol

Mole of Al = 3.346 mol

Step 4 : To find number of atoms of Zn and Al .

In 1 mole of any element , the number of atoms present is 6.022 x 10²³ atoms present .

Hence ,

Number of atoms of Zn = 0.921 * 10²³

And ,

Number of atoms of Al = 20.150 * 10²³

Step 5 : Find atomic fraction of Zn ]

Number of Atoms of Zn = 0.921 * 10²³

Total number of atoms = Atoms of Zn + Atoms of AL

= 0.921 * 10²³ + 20.150 * 10²³ = 21.071 * 10²³

Plugging these values in formula of atomic fraction =>

= 0.0437 * 100

Atomic fraction of Zn = 4.37

i believe it is-

d.) gravity pulled particles of dust and gas together to form planets.

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.