Answer:
GN-z11 is the oldest
Explanation:
GN-z11 has a spectroscopic redshift of z = 11.09, which corresponds to a proper distance of approximately 32 billion light-years
Answer:
.The concentration of N2O4(g) and the concentration of NO2(g) must be constant.
Explanation:
N2O4(g)<--------> 2NO2(g)
At equilibrium, all the concentrations of species involved in the equilibrium expression remain constant. This is because, at equilibrium, the rate of forward reaction equals the rate of reverse reaction. The concentration of the system does not change with time. The relative concentration of each specie, remain steady at equilibrium.
This is the equation balanced:
<span>BaCl2(aq) + Na2CO3(aq) = BaCO3(s) + 2 NaCl(aq)
Then the coefficient in front of Na Cl is 2.
Answer: 2
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Answer 1)
True
Explanation : To achieve an octet state in valence energy level, an oxygen atom will gain two electrons because as per the definition of octet rule, "The atoms<span> of mainly main-group elements tends to get combined in such a way that each </span>atom gets eight electrons in its last valence<span> shell, giving it the nearest same </span>electron<span> configuration as a noble gas". </span>
<span>
</span>So, in the case of oxygen which has 8 electrons and it will accommodate 2 electrons in its first shell and rest 6 in its last valence shell. In order to achieve the octet state it's easier for the atom to gain 2 electrons rather than giving up rest 6 electrons. Hence, it is true that it gains 2 electrons to complete the octet state.
Answer 2)
True
Explanation : The electronic configuration of Krypton [Kr] is
The abbreviated form of any element can be written as the nearest noble elemental configuration, along with the remaining extra distributed electrons in other orbitals;
Hence, the electron configuration of Cesium [Cs} is
which can be also written as Cs = [Kr]