He is using the filtration method.
It’s a technique which is used for separation of solids and fluids by putting them through a medium which allows only fluid to pass through, leaving the solids (in this case the soil) alone.
The fluid that passed is called the filtrate.
Answer:
The answer to your question is empirical formula Al₃O₉S
Explanation:
Data
Al = 31.5 %
O = 56.1 %
S = 12.4 %
Process
1.- Look for the atomic masses of the elements
Al = 27 g
O = 16
S = 32
2.- Represent the percentages as grams
Al = 31.5 g
O = 56.1 g
S = 12.4 g
3.- Convert these masses to moles
27 g of Al ----------------- 1 mol
31.5 g ---------------------- x
x = 1.17 moles
16 g of O ---------------- 1 mol
56.1 g of O ------------- x
x = 3.5 mol
32 g of S --------------- 1 mol
12.4 g of S ------------- x
x = 0.39 moles
4.- Divide by the lowest number of moles
Al = 1.17 / 0.39 = 3
O = 3.5 / 0.39 = 8.9 ≈ 9
S = 0.39 / 0.39 = 1
5.- Write the empirical equation
Al₃O₉S
Answer : The correct option is, forms of the same element that differ in the number of neutrons in each atom
Explanation :
Isotopes : It is defined as the forms of same element that have the same number of protons and electrons but differ in the number of neutrons.
For example : Carbon-12, carbon-13 and carbon-14 is an isotopes due to the same number of protons and electrons and different number of neutrons.
Carbon-12
Atomic number = 6
Atomic mass = 12
Atomic number = Number of protons = Number of electrons = 6
Number of neutrons = Atomic mass - Atomic number = 12 - 6 = 6
Carbon-13
Atomic number = 6
Atomic mass = 13
Atomic number = Number of protons = Number of electrons = 6
Number of neutrons = Atomic mass - Atomic number = 13 - 6 = 7
Carbon-14
Atomic number = 6
Atomic mass = 14
Atomic number = Number of protons = Number of electrons = 6
Number of neutrons = Atomic mass - Atomic number = 14 - 6 = 8
Litmus paper turns red in acidic conditions whether its blue or red litmus ,its not NH3 (ammonia) , neither is it barium hydroxide (A) , sodium hydroxide (B) will make it blue or remain blue (depemding on type of paper used ) so it has to be D which is the chemjcal formula for acetic acid , hope this helps !