The answer is A, light and heat energy.
Answer:
The first option
Explanation:
Carbon is a p-block element. It is the 6th element on the periodic table and therefore it has 6 electrons.
The sub-level notation is given as:
1s² 2s² 2p²
The s-sublevel can only accommodate two maximum electrons because it has one orbital. This is why both 1s and 2s contains just two electrons each. When both sub-levels are filled, we have just 2 remaining electrons to fill the p-sublevel.
The p-sublevel contains 3 orbitals and can accommodate a maximum of 6 electrons. But we have just 2 electrons. According to Hund's rule of maximum mulitiplicity, electrons will go into degenerate orbitals singly before paring up. Therefore, the first two orbitals in p-sublevel will receive an electron each.
This is why the first model fits.
Answer:

Explanation:
Hello there!
In this case, since redox reactions are characterized by the presence of a reduction reaction, whereby the oxidation of the element decreases, and an oxidation reaction whereby the oxidation of the element increases.
In such a way, for the given chemical equation, we can see Fe is increasing its oxidation state from 2+ to 3+, which means it is oxidized. On the flip side, Mn is being reduced from 7+ (MnO₄⁻) to 2+ and this, the reduction half-reaction is:

Whereas five electrons are carried.
Regards!
Explanation:
The formula mass of a molecule (also known as formula weight) is the sum of the atomic weights of the atoms in the empirical formula of the compound.
a. NO2
N = 14
O = 16
NO2 = 14 + (16 * 2) = 46 amu
b. C4H10
Empirical formular = C2H5
C = 12
H = 1
C2H5 = (12*1) + (1*5) = 12 + 5 = 17 amu
c. C6H12O6
Empirical formular = CH2O
C = 12
H = 1
O = 16
C2H5 = 12 + (1*2) + 16 = 30 amu
d MgBr2
Mg = 24
Br = 80
MgBr2 = 24 + (80*2) = 184 amu
e. HNO2
H = 1
N= 14
0 = 16
HNO2 = 1 + 14 + (16*2) = 47 amu
f. CBr4
C= 12
Br = 80
CBr4 = 12 + (80*4) = 332 amu
g. Cr(NO3)3
Cr = 52
N = 14
O = 16
Cr(NO3)3 = 52 + 3[14 + (3*16)] = 238 amu