Answer:
Explanation:
Both diamond and graphite are made entirely out of carbon.In a diamond, the carbon atoms are arranged tetrahedrally. Each carbon atom is attached to four other carbon with a C-C-C bond angle of 109.5 degrees. It is a strong, rigid three-dimensional structure that results in an infinite network of atoms. This accounts for diamond's hardness, extraordinary strength and durability and gives diamond a higher density than graphite. Because of its tetrahedral structure, diamond also shows a great resistance to compression. Diamond will scratch all other materials and is the hardest material known. It is the best conductor of heat that we know, conducting up to five times the amount that copper does. Diamond also conducts sound, but not electricity; it is an insulator, and its electrical resistance, optical transmissivity and chemical inertness are correspondingly remarkable.
The carbon atoms in graphite are also arranged in an infinite array, but they are layered. These atoms have two types of interactions with one another. In the first, each carbon atom is bonded to three other carbon atoms and arranged at the corners of a network of regular hexagons with a 120-degree C-C-C bond angle. These planar arrangements extend in two dimensions to form a horizontal, hexagonal "chicken-wire" array. In addition, these planar arrays are held together by weaker forces. The distance between two layers is longer than the distance between carbon atoms within each layer. This three-dimensional structure accounts for the physical properties of graphite. Unlike diamond, graphite can be used as a lubricant or in pencils because the layers cleave readily. It is soft and slippery, and its hardness is less than diamond . Graphite also has a lower density (2.266 grams per cubic centimeter) than diamond. The planar structure of graphite allows electrons to move easily within the planes. This permits graphite to conduct electricity and heat as well as absorb light and, unlike diamond, appear black in color.
Answer:
All three are present
Explanation:
Addition of 6 M HCl would form precipitates of all the three cations, since the chlorides of these cations are insoluble: 
.
- Firstly, the solid produced is partially soluble in hot water. Remember that out of all the three solids, lead(II) choride is the most soluble. It would easily completely dissolve in hot water. This is how we separate it from the remaining precipitate. Therefore, we know that we have lead(II) cations present, as the two remaining chlorides are insoluble even at high temperatures.
- Secondly, addition of liquid ammonia would form a precipitate with silver:
![AgCl (s) + 2 NH_3 (aq) + H_2O (l)\rightarrow [Ag(NH_3)_2]OH (s) + HCl (aq)](https://tex.z-dn.net/?f=AgCl%20%28s%29%20%2B%202%20NH_3%20%28aq%29%20%2B%20H_2O%20%28l%29%5Crightarrow%20%5BAg%28NH_3%29_2%5DOH%20%28s%29%20%2B%20HCl%20%28aq%29)
; Silver hydroxide at higher temperatures decomposes into black silver oxide: ![2 [Ag(NH_3)_2]OH (s)\rightarrow Ag_2O (s) + H_2O (l) + 4 NH_3 (g)](https://tex.z-dn.net/?f=2%20%5BAg%28NH_3%29_2%5DOH%20%28s%29%5Crightarrow%20Ag_2O%20%28s%29%20%2B%20H_2O%20%28l%29%20%2B%204%20NH_3%20%28g%29)
. - Thirdly, we also know we have
in the mixture, since addition of potassium chromate produces a yellow precipitate: 
. The latter precipitate is yellow.
Answer:
Umm i dont know but i think atomic nucleus
Explanation:
Answer:
Second option. 3
Explanation:
In order to balance a equation you need to have the same amount of atoms/moles in both sides.
Na₃PO₄ + _ HCl → 3NaCl + H₃PO₄
In reactant side we have 3 Na and we have the same amount in product side.
We also have 1 P and 4 O in both sides of the equation.
As we have 3 moles of NaCl in product side, this means we have:
NaCl → Na⁺ + Cl⁻
3 moles of Na⁺ and 3 moles of Cl⁻. In conclussion we need 3 moles of Cl⁻ in reactant side.Then, the stoichiometry of HCl must be, 3.
3 moles of HCl means that we have 3 moles of protons (H⁺).
HCl → H⁺ + Cl⁻
If you see the phosphoric acid, we also have 3 moles of protons.
H₃PO₄ → 3H⁺ + PO₄³⁻
Complete balanced equation is:
Na₃PO₄ + 3HCl → 3NaCl + H₃PO₄
