A compound light microscope is a microscope with more than one lens and its own light source. In this type of microscope, there are ocular lenses in the binocular eyepieces and objective lenses in a rotating nosepiece closer to the specimen.
Although sometimes found as monocular with one ocular lens, the compound binocular microscope is more commonly used today.
Answer:
The answer to your question is: Excess oxygen = 2.3 mol
Explanation:
Data
ZnS = 5 mol
O2 = 9.8 mol
Excess reactant = ?
Balanced reaction
2ZnS(s) + 3O2(g) → 2ZnO(s) + 2SO2(g)
MW ZnS = 65 + 32 = 97 x 2 = 194 g
MW O2 = 16 x 6 = 96 g
2 mol of ZnS ------------------- 3 mol O2
Ratio from the reaction = 3 mol O2/ 2 mol ZnS
= 1.5
Ratio from the quantities in the experiment = 9.8 mol O2 / 5 mol of ZnS
= 1.96
Excess reactant = Oxygen because the ratio increases
2 mol of ZnS ------------------- 3 mol O2
5 mol of ZnS ------------------- x
x = (5 x 3) / 2
x = 7.5 mol of O2
Excess Oxygen = 9.8 mol - 7.5 mol
Excess oxygen = 2.3 mol
Given :
The atomic number of Arsenic (As) is 33.
The average atomic mass is 74.92 amu.
To Find :
A neutral arsenic atom will have protons.
Solution :
We know, atomic mass is the sum of number of protons and neutrons.
Also, atomic number is the number of protons present in an atom.
Therefore, a neutral arsenic atom will have 33 protons.