Answer:
157.79 g
Explanation:
The definition of molality is:
- molality = moles of solute / kilogram of solvent
This means that in a 2.7 molal solution, there are 2.7 moles of NaCl per kilogram of water.
So now w<u>e convert those 2.7 moles of NaCl to grams</u>, using its <em>molar mass</em>:
- 2.7 mol * 58.44 g/mol = 157.79 g
Neptune planet has the coldest surface temperature
<u>Explanation:</u>
With temperatures falling to -218°C in Neptune’s upper atmosphere, the planet is one of the coolest in our Solar System. Neptune is the most faraway planet from the sun. Astronomers have speculated that Neptune's huge internal temperature and the transfer of heat between the core and outer layers might be the cause why Neptune isn't significantly more chill than Uranus.
Pressures in this area range between 1 and 5 bars and the temperature reaches a high of 72 K. At this temperature, states are becoming for methane to condense, and clouds of ammonia and hydrogen sulfide are thought to form. At its core, Neptune reaches temperatures of up to 7273 K which is equivalent to the surface of the sun.
<u><em>on the basis of the reaction of heat in plastic , their are two types of plastics : </em></u>
<h2><u>
<em>Thermoplastic & Thermosetting plastics </em></u></h2>
<u><em>Thermoplastics : Plastics which easily get deformed (become soft )on heating and also get bend easily are known as thermoplastics . </em></u>
<u><em>examples : polythene , polyvinyl chloride and polystyrene .</em></u>
<u><em>thermosetting plastics : plastics which once moulded into a shape do not become soft on heating and cannot be moulded again are called thermosetting plastics .</em></u>
<u><em>examples : bakelite , melamine and formica</em></u>
<span>You have to use a Newman projection to make sure that the H on C#2 is anti-coplanar with the Br on C#1. (Those are the two things that are going to be eliminated to make the alkene.)
My Newman projection looks like this when it's in the right configuration:
Front carbon (C#2) has ethyl group straight up, H down/left, and CH3 down/right
Back carbon (C#1) has H straight down, Ph up/left, and Br up/right.
Then when you eliminate the H from C#2 and the Br from C#1, you will have Ph and the ethyl group on the same side of the molecule, and you'll have the remaining H and CH3 on the same side of the molecule.
This is going to give you (Z)-2-methyl-1-phenyl-1-butene.</span>
P = 1.5atm ≈ 1519.88hPa
V = 8.56L
R = 83.1 [hPa*L] / [mol*K]
T = 0°C =273K
pV = nRT |:RT
n = pV / RT
n = [1519.88hPa*8.56L] / [83.1 [hPa*L] / <span>[mol*K] * 273K]
n </span>≈ <u>0.57mol</u><span><u> </u></span>
