Answer:
a) ethanol is dehydrated by concentrated sulphuric acid to yield ethene
b) Concentrated phosphoric(V) acid, H3PO4, can be used instead of sulphuric acid
Explanation:
Ethene is prepared in the lab by heating ethanol with concentrated sulphuric acid at 170°C. The mixture contains 1:2 volume ratio of the ethanol and concentrated acid. Ethylhydrogentetraoxosulphate VI is first formed and then decomposes to yield ethene and sulphuric acid.
The overall reaction is akin to the dehydration of ethanol. As is easily seen above; this is a two stage reaction. The first stage is the formation of the ester, the second stage involves the dehydration of the ester to yield ethene. The ethene gas is passed through concentrated sodium hydroxide to remove any gaseous impurities present and then it is collected over water.
Concentrated phosphoric(V) acid, H3PO4, can be used instead of concentrated sulphuric acid as a dehydrating agent in the laboratory preparation of ethene.
Answer:
a. 50ml b.10ml c. 6.097ml d. 190.1 ml
Explanation:
According to Boyle's law
Volume is inversely proportional to pressure at constant temerature
Mathematically
P1V1=P2V2
P1=Initial pressure=0.8atm
V1=Initial volume=25ml
making V2 the subject
at 0.4atm P2=0.4 atm,
V2=25×0.8/0.4
=50ml
at 2 atm V2=25×0.8/2
=10 ml
1mmHg=0.00131579
2500mmHg=3.28 atm
At 3.28 atm,V2=25×0.8/3.28
=6.097 ml
at 80.0 torr
1 torr=0.00131579
80 torr=0.1052 atm
at 0.1048 atm V2=25×0.8/0.1048
=190.1 ml
Answer:
Al, Zn, Fe, Sn, Pb.
Explanation:
The arrangement can be done using the infomation on electrochemical series of metals.
The electrochemical series is built up by arranging various metals in order of their standard electrode potentials (or reactivity). The most negative E° values are placed at the top of the electrochemical series, and the most positive at the bottom. some of the metals are arranged as follws; K, Na, Ca, Mg, Al, Zn, Fe, Sn, Pb, H, Cu, Hg, Ag, Au (decreasing reactivity)
One can use the following to remember the arrangement: king Nathan Can Manage All Zone Freely Since Probably He Can Handle All Ages.
Answer : Molecular compounds dissolve in water by means of dipole-dipole attractions and hydrogen bond attractions. These attractions between the molecular compound and water don't form ions when a molecular compound dissolves.
Explanation: I hoped that helped,
D. g ( x ) = 4x^2
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