1. The answer is option E, that is None of the above is correct.
As a polymer becomes more crystalline,
its melting point doesn't decreases, its density doesn't decreases, its stiffness doesn't decreases and its yield stress doesn't decreases.
2. The answer is option B, that is the molecules are arranged in sheets, with their long axes parallel and their ends aligned as well.
In the smectic A liquid-crystalline phase, molecules are arranged in sheets, with their long axes parallel and their ends aligned as well.
3. For a substitutional alloy to form, the two metals combined must have similar atomic radii and chemical bonding properties.
Answer:
0.025 L
Explanation:
The production of oxygen in the electrolysis of water is;
4OH^-(aq) -----> 2H2O(l) + O2(g) + 4e
Since 1 F = 96500C
molar volume of a gas = 22.4 L
From the reaction equation;
4 * 96500 C yields 22.4 L of oxygen
(3 * 60 * 60 * 0.0400) C yields (3 * 60 * 60 * 0.0400) * 22.4/4 * 96500
= 9676.8/386000
= 0.025 L
Explanation:
For the first part,
Reaction equation:
N₂ + 3H₂ → 2NH₃
Given:
Number of moles of NH₃ = 6 moles
Unknown:
Number of moles of N₂ = ?
Solution:
N₂ + 3H₂ → 2NH₃;
From the reaction above, we solve from the known specie to the unknown. Ensure that the equation is balanced;
2 moles of NH₃ is produced from 1 mole of N₂
6 moles of NH₃ will be produced from mole of N₂
= 3moles of N₂
The number of moles of N₂ is 3 moles
ii.
Given parameters:
Number of moles of sulfur = 2.4moles
Molar mass of sulfur = 32.07g/mol
Unknown:
Mass of sulfur = ?
Solution:
The number of moles of any substance can be found using the expression below;
Number of moles =
Mass of sulfur = number of moles of sulfur x molar mass
Insert the parameters and solve;
Mass of sulfur = 2.4 x 32.07 = 76.97g
80.1 g* (1 cm^(3)/ 2.70 g)= 29.666666... cm^(3).
The calculated volume should have 3 significant figures, so the final answer is 2.97*10^(1) cm^(3)
Hope this helps~