We call these reactive elements, becausethese atoms really like to follow the buddysystem and form bonds with other atoms.Noble gases, however, don't have thisproblem. Their outer shells are filled to the max, so they don't need to bond or react with any other atoms.
The oxidation number of chlorine in the reactant can be determined by K ion and O ion. K ion is +1 and O ion is -2. And the Cl is +5. The gas has the greatest entropy and the solid has the least. In the production, there are solid and gas. So it has more entropy than the reactants with solid only.
Answer:
B
Explanation:
Mars atmosphere contains mainly carbon iv oxide, but the greenhouse effect as subdued as there is so little CO2 overall.
Venus as a planet contains 96.5% of carbon iv oxide. it doesn't contain water which can trap the CO2 as we have on earth where the oceans are able to trap the CO2 present and subdue the greenhouse effect. This inability to trap CO2 in Venus prevents infrared rays from escaping and with the fact the Venus is closer to the sun than earth and mars, its surface it extremely hot.
Answer:
Option B is correct.
4
Explanation:
We know that an atom consist of electron, protons and neutrons. Protons and neutrons are present with in nucleus while the electrons are present out side the nucleus.
All these three subatomic particles construct an atom. A neutral atom have equal number of proton and electron. In other words we can say that negative and positive charges are equal in magnitude and cancel the each other. For example, if neutral atom has 6 protons than it must have 6 electrons. The sum of neutrons and protons is the mass number of an atom while the number of protons are number of electrons is the atomic number of an atom.
In given problem we are given with 2 neutrons of helium. We know that the atomic number of He is 2. Thus Mass number of He is,
Number of neutrons + number of proton
2 + 2 = 4
Thus, option B is correct.
The equation Eºcell = 0.0592/n logK must be used to find n and also Eºcell
2 Al(s) + 3 Mg2+(aq) → 2 Al3+(aq) + 3 Mg(s) Al3+ +3e- --> Al Eº = -1.66 V Mg2+ +2e- -->Mg Eº = -2.37V
To balance the equation, 6 moles of electrons must be transferred (2 Al and 3 Mg). This will be the value of n in the equation.
To find Eºcell, you need the reduction potentials which should be given in a table, and given above. Eºcell = -1.66 - (-2.37) = 0.71 V log K = Eºcell x n/0.0592 = 0.71 x 6/0.0592 log K = 71.95 K = 10^71.95 K = 1.1x10^72
