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Answer:
Elements
Explanation:
The <u> elements</u> which are represented by a single uppercase letter, or represented by an uppercase letter followed by a lowercase letter. This tells you the types of <u>elements</u> in the compound.
Elements are one of the simplest chemical substances that cannot be decomposed in a chemical reaction or by any chemical means. They are made up of small indivisible particles called atoms, all having the same number of protons.
Answer:
19.79%
Explanation:
mass % = (mass solute / total mass) * 100
total mass = 129.54 + 525 = 654.54
solute = C6H12O6
(129.54/654.54) = .1979
.1979 * 100 = 19.79%
Answer:
See the answer below
Explanation:
The best approach would be to <u>pour the liquid from the large reagent bottle into a small-size beaker or reagent bottle first</u>, before measuring the required quantity out into the reaction vessel. This is necessary in order to maintain safety in the laboratory.
Pouring the liquid directly from the large reagent bottle into the measuring cylinder or directly into the reaction bottle can compromise safety in the laboratory. The liquid might splash out and cause harm to the handler or create other harmful circumstances in the laboratory.
Answer:
3.74g of ethylene glycol must be added to decrease the freezing point by 0.400°C
Explanation:
One colligative property is the freezing point depression due the addition of a solute. The equation is:
ΔT=Kf*m*i
<em>Where ΔT is change in temperature = 0.400°C</em>
<em>Kf is freezing point constant of the solvent = 1.86°C/m</em>
<em>m is molality of the solution (Moles of solute / kg of solvent)</em>
<em>And i is Van't Hoff constant (1 for a nonelectrolyte)</em>
Replacing:
0.400°C =1.86°C/m*m*1
0.400°C / 1.86°C/m*1 = 0.215m
As mass of solvent is 280.0g = 0.2800kg, the moles of the solute are:
0.2800kg * (0.215moles / 1kg) = 0.0602 moles of solute must be added.
The mass of ethylene glycol must be added is:
0.0602 moles * (62.10g / mol) =
3.74g of ethylene glycol must be added to decrease the freezing point by 0.400°C
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