Metallic bonds are forces that holds atoms together in a marlin substance
Eeletrolysis is a method of removing individual hairs from the face or body .Medical electrolysis devices destroy the growth center of the hair with chemical or heat energy.After a very fine probe is inserted into the hair follicle, the hair is removed with tweezers
The full question asks to decide whether the gas was a specific gas. That part is missing in your question. You need to decide whether the gas in the flask is pure helium.
To decide it you can find the molar mass of the gas in the flask, using the ideal gas equation pV = nRT, and then compare with the molar mass of the He.
From pV = nRT you can find n, after that using the mass of gass in the flask you use MM = mass/moles.
1) From pV = nRT, n = pV / RT
Data:
V = 118 ml = 0.118 liter
R = 0.082 atm*liter/mol*K
p = 768 torr * 1 atm / 760 torr = 1.0105 atm
T = 35 + 273.15 = 308.15 K
n = 1.015 atm * 0.118 liter / [ 0.082 atm*liter/K*mol * 308.15K] =0.00472 mol
mass of gas = mass of the fask with the gas - mass of the flasl evacuated = 97.171 g - 97.129 g = 0.042
=> MM = mass/n = 0.042 / 0.00472 = 8.90 g/mol
Now from a periodic table or a table you get that the molar mass of He is 4g/mol
So the numbers say that this gas is not pure helium , because its molar mass is more than double of the molar mass of helium gas.
The correct answer is B. The shape of a molecule where three pairs of electrons are shared is a trigonal planar. This is characterized by one central atom and three atoms forming an equilateral triangle which is bonded to the central atom.
Answer:
a. minimum voltage that must be supplied for a redox reaction to occur
c. always equal to Eanode - Ecathode
Explanation:
In an electrolytic cell; The electromotive force(the maximum standard potential difference) of the cell formed by the system is defined as the standard electrode potential of the right handed electrode minus the standard electrode potential of the left hand electrode. (i.e
)
As we all known that the process by which chemical energy is being converted to electrical energy is called the Electrochemical cell. It consists of two half cells , an oxidation half cell reaction and a reduction half-cell reaction.The overall redox reaction results in a flow of electrons in an electric current which is produced by a minimum voltage.
Therefore, option a and c are both correct.