Tough question, I would suggest using Google maybe, or just plain out asking your science teacher.
For the crystallization purpose the combination of solvent process is known to be an effective process. But the solvent pair one have to choose crucially. The solvent which is completely in soluble into the other solvent can not work as a good solvent pair for the crystallization. The crystallization of any compound by the solvent pair process is depend upon the slow diffusion of a less polar solvent to the polar solvent or vice-versa.
If a compound is soluble in a polar solvent the slow diffusion of relatively low polar solvent will make crystal of the compound. But anyhow the solvents which are completely not immiscible to each other will not work for the purpose. Thus diethyl ether and water solvent pair can not be used for the crystallization process.
Answer:
NH₃
Explanation:
mass H = 6.10 grams
mass N = 28.00 grams
mass cpd = (6.10 + 28.00)grams = 34.10 grams
%H/100wt = (6.10/34.10)100% = 17.9% w/w
%N/100wt = (28.00/34.1)100% = 82.1% w/w
%/100wt => grams/100wt => moles => ratio => reduce => emp ratio
%H/100wt = 17.9% w/w => 17.9g => (17.9/1)moles = 17.9 moles H
%N/100wt = 82.1% w/w => 82.1g => (82.1/14)moles = 5.9 moles N
Ratio N:H => 17.9 : 5.9
Reduce mole ratio (divide by smaller mole value) => 17.9/5.9 : 5.9/5.9
=> 3HY:1H empirical ratio => empirical formula NH₃ (ammonia)
Answer:
Different types of hot or cold items can be stored in a thermos and power cannot enter or exit the system when the thermos lid is tightly closed
Explanation:
Closed systems are those that do not interact or do not exchange energy with the environment that surrounds them, that is why internal temperatures and conditions are maintained.
The human body is an open system, that is, it would be the opposite of the thermos since we constantly exchange energy with the environment through sweating, emission of gases, urine, feces, and the ingestion of food.
Thermoses are systems specially created to maintain a medium, it will be maintained if its lid is hermetically closed to prevent heat leakage or entry in situations of cold fluids.
The amount of heat lost by granite is equal to the amount
of heat gained by water. Therefore their change in enthalpies must be equal.
The opposite in sign means that one is gaining while the other is losing
ΔH granite = - ΔH water
ΔH is the change in enthalpy experienced by a closed object
as it undergoes change in energy. This is expressed mathematically as,
ΔH = m Cp (T2 – T1)
Given this information, we can say that:
12.5 g * 0.790 J / g ˚C * (T2 – 82 ˚C) =
- 25.0 g * 4.18 J / g ˚C
* (T2 – 22 ˚C)
9.875 (T2 – 82) = 104.5 (22 – T2)
9.875 T2 – 809.75 = 2299 – 104.5 T2
114.375 T2 = 3108.75
T2 = 27.18 ˚C
The temperature of 2 objects after reaching thermal
equilibrium is 27.18 ˚<span>C.</span>
