Answer:
d. Copper (II) sulfate
Explanation:
Given data:
Mass of Al = 1.25 g
Mass of CuSO₄ = 3.28 g
What is limiting reactant = ?
Solution:
Chemical equation:
2Al + 3CuSO₄ → Al₂ (SO₄)₃ + 3Cu
Number of moles of Al:
Number of moles = mass/molar mass
Number of moles = 1.25 g/ 27 g/mol
Number of moles = 0.05 mol
Number of moles of CuSO₄:
Number of moles = mass/molar mass
Number of moles = 3.28 g/ 159.6 g/mol
Number of moles = 0.02 mol
now we will compare the moles of reactant with product.
Al : Al₂ (SO₄)₃
2 : 1
0.05 : 1/2×0.05=0.025 mol
Al : Cu
2 : 3
0.05 : 3/2×0.05 = 0.075 mol
CuSO₄ : Al₂ (SO₄)₃
3 : 1
0.02 : 1/3×0.02=0.007 mol
CuSO₄ : Cu
3 : 3
0.02 : 0.02
Less number of moles of reactants are produced by CuSO₄ thus it will act as limiting reactant.
The statement that would be held true for an acidic solution would be option C. The molarity or concentration of the hydronium ions would be more than that of the hydroxide ions. As the acidity of a solution increases as there is a greater amount of H+ or H3O+ ions present, within it. This is will give us a low pH and thus is quite acidic.
If the concentrations of the OH- and H3O+ are the same then the solution would be neutral, and if the opposite is true. The concentration of OH- is more than H3O+ than the solution would be basic.
Answer: The correct option is D.
Explanation: Nonmetallic minerals are the chemical elements from which no new product can be formed when they are melted. For Example: Sand, marble etc..
For the given options:
Option A: Wood is a type of cellulose and is not considered as a nonmetallic mineral resource.
Option B: Iron is an element because it is the smallest substance which cannot be broken down. It is not considered as a nonmetallic mineral resource.
Option C: Coal is a mixture of carbon compounds. This is very close to mineral but is an organic mineral because it contains carbon atom. Hence, it is not considered as a nonmetallic mineral resource.
Option D: Aggregate is formed by the collection of particles forming a whole mass. This is a non-metallic resource as it cannot form any new product.
Hence, the correct option is D.
Chlorophyll, it is the pigment in plants that absorbs light in photosynthesis
<h2>
Which source would be most reliable for gathering experimental results related to a new compound’s molecular mass : A textbook that lists molecular masses of similar compounds</h2>
Explanation:
Atom:
It is a smallest particle of an element which may as may not have independent existence.
The are very small in size.
Their size is measured in unit nm (nanometer)
1nm – 10⁻⁹ m.
hydrogen atom is smallest of all size is only 10⁻¹⁰ nm
Atoms are represented by symbols (given by berzelius )
Atomic mass of element-
Active atomic mass of atom can’t be measured but relative atomic mass can be known.
I.e. relative atomic mass of an atom of element is defined as average relative mass of atom as compared with atom of 612c taken as 12u.
Atomic mass – no. Of times one atom of he element is heavier then 1/12th of c atom.
Molecule
It is smallest particle of an element or compound which is able to exist independently.
Some element exist as
Diatomic molecuel eq:- O₂
Triatomic molecule eq:- O₃
¬
So,
Atomicity – is no. of atoms in a molecule of an element.
Some more examples:- phosphorous P4 (tetra atomic)
sulphur S8 (poly-atomic)
nitrogen N2 (diatomic)
Molecular mass
It is the mass of molecule that is obtained by adding masses of atoms multiplied with number of atoms of each type .