Answer:
the molar mass is the mass of a given chemical element or chemical compound divided by the amount of substance
The oxidation number of an element is the number of electrons that are gained or lost by the element to form a chemical bond.
the net oxidation number of the ion is its charge.
compound (NH₄)₂Cr₂O₇ is made of cation - NH₄⁺ and anion - Cr₂O₇²⁻
oxidation number of ion - -2
(oxidation number of Cr x 2 Cr atoms) +(oxidation number of O x 7 O atoms )= -2
oxidation number of Cr = y
oxidation number of O = -2
(y x 2) + (-2 x 7) = -2
2y - 14 = -2
2y = 12
y = + 6
therefore oxidation number of Cr is +6
Answer:
Metallic bonds
Explanation:
Metallic bonds joins atoms of metals and atoms of alloys together. The copper used in making pennies is a metallic substance so it contains metallic bonds.
- The formation of this bond type is predicated on the large atomic radius, low ionization energy and large number of electrons in the valence shell.
- The bond is an attraction between the positive nuclei of all closely packed atoms in the lattice and the electron cloud.
- The electron cloud is jointly formed by all the atoms by losing their outermost shell electrons.
This way the bond in pennies are metallic in nature.
Answer:
Conduction, Convection, and Radiation .......
Coal releases carbon dioxide when burned. The reaction looks like this:
C(s)+O₂(g)→CO₂(g)
I hope this helps. Let me know in the comments if anything is unclear.