Lowery-Bronsted theory is applied here. Acc. to this theory Base accepts protons and Acids donate proton.
Part 1:
Aniline is less basic than ethylamine because the lone pair on nitrogen (which accepts proton) is not localized. It resonates throughout the conjugated system of phenyl ring. Hence due to unavailability of electrons for accepting proton it is less basic compare to ethylamine. In ethyl amine the lone pair of electron is localized and available to abstract proton.
Part 2:
In this case the alkyl groups attached to -NH₂ (in ethylamine) and -O⁻ (in ethoxide are same (i.e. CH₃-CH₂-). Ethoxide is more basic than ethylamine because ethoxide is a conjugate base of ethanol (pKa value of ethanol = 15.9 very weak acid) and the conjugate base of weak acid is always a strong base. Secondly, the oxygen atom more Electronegative than Nitrogen atom can attract more electron cloud from alkyl group as compared to Nitrogen in ethylamine. Hence, oxygen in ethoxide attains greater electron cloud than the nitrogen in ethylamine. Therefore, it is more basic than ethylamine.
Analogous structures are those structures in different species which perform the same function, have similar appearance and structure but are not evolved together; therefore do not share a common ancestor. Homologous and analogous organs video explains in a simple way.
Answer:
Jeweler B = more accurate
Jeweler A = more precise
Error:
0.008, 0
% error :
0.934% ; 0
Explanation:
Given that:
True mass of nugget = 0.856
Jeweler A: 0.863 g, 0.869 g, 0.859 g
Jeweler B: 0.875 g, 0.834 g, 0.858 g
Official measurement (A) = 0.863 + 0.869 + 0.859 = 2.591 / 3 = 0.864
Official measurement (B) = 0.875 + 0.834 + 0.858 = 2.567 / 3 = 0.8556
Accuracy = closeness of a measurement to the true value
Accuracy = true value - official measurement
Jeweler A's accuracy :
0.856 - 0.864 = - 0.008
Jeweler B's accuracy :
0.856 - 0.856 = 0.00
Therefore, Jeweler B's official measurement is more accurate as it is more close to the true value of the gold nugget.
However, Jeweler A's official measurement is more precise as each Jeweler A's measurement are closer to one another than Jeweler B's measurement which are more spread out.
Error:
Jeweler A's error :
0.864 - 0.856 = 0.008
% error =( error / true value) × 100
% error = (0.008/0.856) × 100% = 0.934%
Jeweler B's error :
0.856 - 0.856 = 0 ( since the official measurement as been rounded to match the decimal representation of the true value)
% error = 0%
First we determine the
moles CaCl2 present:
525g / (110.9g/mole) =
4.73 moles CaCl2 present
Based on stoichiometry,
there are 2 moles of Cl for every mole of CaCl2:<span>
(2moles Cl / 1mole CaCl2) x 4.73 moles CaCl2 = 9.47 moles Cl </span>
Get the mass:<span>
<span>9.47moles Cl x 35.45g/mole = 335.64 g Cl</span></span>
Answer:
11.3 g of
are produced from 36.0 g of 
Explanation:
1. The balanced chemical equation is the following:

2. Use the molar mass of the
, the molar mass of the
and the stoichiometry of the balanced chemical reaction to find how many grams of
are produced:
Molar mass
= 18
Molar mass
= 17

Therefore 11.3 g of
are produced from 36.0 g of 