Ultraviolet as ultraviolet light waves are around 420 nm like stated in the photo
What are the answers choices?
Answer:
1.387 moles
Explanation:
Step 1:
The balanced equation for the reaction. This is illustrated below:
4Fe + 3O2 —> 2Fe2O3
Step 2:
Determination of the number of mole of Fe in 155.321g of Fe. This can be achieved by doing the following:
Mass of Fe = 155.321g
Molar Mass of Fe = 56g/mol
Number of mole of Fe =?
Number of mole = Mass/Molar Mass
Number of mole of Fe = 155.321/56
Number of mole of Fe = 2.774 mol
Step 3:
Determination of the number of mole of rust (Fe2O3) produced. This is illustrated below:
From the balanced equation above,
4 moles of Fe produced 2 moles of Fe2O3.
Therefore, 2.774 moles of Fe will produce = (2.774 x 2)/4 = 1.387 moles of Fe2O3.
Therefore, 1.387 moles of rust (Fe2O3) is produced from the reaction
Answer:
The atomic mass of element is 65.5 amu.
Explanation:
Given data:
Abundance of X-63 = 50.000%
Atomic mass of X-63 = 63.00 amu
Atomic mass of X-68 = 68.00 amu
Atomic mass of element = ?
Solution:
Abundance of X-68 = 100-50 = 50%
Average atomic mass = (abundance of 1st isotope × its atomic mass) +(abundance of 2nd isotope × its atomic mass) / 100
Average atomic mass = (50×63)+(50×68) /100
Average atomic mass = 3150 + 3400 / 100
Average atomic mass = 6550 / 100
Average atomic mass = 65.5 amu.
The atomic mass of element is 65.5 amu.