Answer:
Explanation:
Melting and boiling point variations are not clear (do not have uniform pattern) in periodic table. But we can see, some elements have higher melting and boiling points and some have less. Here we study melting and boiling points of s, p, d blocks elements. IVAth group elements (C,Si) show high melting and boiling points because they have covalent gigantic lattice structures.
Answer: Magnesium
Explanation:
Galvanic cell is a device which is used for the conversion of the chemical energy produces in a redox reaction into the electrical energy.
The standard reduction potential for magnesium and zinc are as follows:
![E^0_{[Mg^{2+}/Mg]}= -2.37V](https://tex.z-dn.net/?f=E%5E0_%7B%5BMg%5E%7B2%2B%7D%2FMg%5D%7D%3D%20-2.37V)
![E^0_{[Zn^{2+}/Zn]}=-0.76V](https://tex.z-dn.net/?f=E%5E0_%7B%5BZn%5E%7B2%2B%7D%2FZn%5D%7D%3D-0.76V)
Reduction takes place easily if the standard reduction potential is higher (positive) and oxidation takes place easily if the standard reduction potential is less (more negative).
Here Mg undergoes oxidation by loss of electrons, thus act as anode. Zinc undergoes reduction by gain of electrons and thus act as cathode.
Thus magnesium gets oxidized.
find mol of N2 present using gas law equation
PV = nRT
P = pressure = 688/760 = 0.905 atm.
V = 100mL = 0.1L
n = ???
R = 0.082057
T = 565+273 = 838
Substitute:
0.905*0.1 = n*0.082057*838
n = 0.0905 / 68.76
n = 0.00132 mol N2
Molar mass N2 = 28 g/mol
0.00132 mol = 0.00132*28 = 0.037g N2 gas
Answer:
a. C: +3 ; b. N: +5 ; c. S:+6 ; d. C: +4; e. Mn: +7 ; f. Cr: +6.
Explanation:
Global charges in molecules is 0
You sum all the oxidation states to determine the oxidation state for the compound.
Na₂C₂O₄ → Sodium oxalate → Global charge: 0
Oxidation state for C: +3
HNO₃ → Nitric acid → Global charge: 0
Oxidation state for N: +5
H₂SO₄ → Sulfuric acid → Global charge: 0
Oxidation state for S: +6
HCO₃⁻ → Bicarbonate → Global charge: -1, this is an anion
Oxidation state for C: +4
KMnO₄ → Potassium permanganate → Global charge: 0
Oxidation state for Mn: +7
Cr₂O₇⁻ → Anion dichromate → Global charge: -2
Oxidation state for Cr: +6
