Answer:
The high melting point is also consistent with its description as an ionic solid. In the crystal, each S2− ion is surrounded by an octahedron of six Ca2+ ions, and complementarity, each Ca2+ ion surrounded by six S2− ions.
Explanation:
You can use the periodic table to predict whether an atom will form an anion or a cation, and you can often predict the charge of the resulting ion. Atoms of many main-group metals lose enough electrons to leave them with the same number of electrons as an atom of the preceding noble gas. To illustrate, an atom of an alkali metal (group 1) loses one electron and forms a cation with a 1+ charge; an alkaline earth metal (group 2) loses two electrons and forms a cation with a 2+ charge, and so on. For example, a neutral calcium atom, with 20 protons and 20 electrons, readily loses two electrons. This results in a cation with 20 protons, 18 electrons, and a 2+ charge. It has the same number of electrons as atoms of the preceding noble gas, argon, and is symbolized Ca2+. The name of a metal ion is the same as the name of the metal atom from which it forms, so Ca2+ is called a calcium ion.
When atoms of nonmetal elements form ions, they generally gain enough electrons to give them the same number of electrons as an atom of the next noble gas in the periodic table. Atoms of group 17 gain one electron and form anions with a 1− charge; atoms of group 16 gain two electrons and form ions with a 2− charge, and so on. For example, the neutral bromine atom, with 35 protons and 35 electrons, can gain one electron to provide it with 36 electrons. This results in an anion with 35 protons, 36 electrons, and a 1− charge. It has the same number of electrons as atoms of the next noble gas, krypton, and is symbolized Br−. (A discussion of the theory supporting the favored status of noble gas electron numbers reflected in these predictive rules for ion formation is provided in a later chapter of this text.)
Due to the high strength of iron compared to that of barium and phosphorus the nails are made of iron.
Though iron oxidizes to form rust on reacting with water but it does not explode. Whereas barium reacts vigorously with water with evolution of hydrogen gas. Barium on reacting with other nonmetals results in the formation of poisonous substances. Phosphorus is never found in its pure form in nature and is combustible.
Hence, nails are made up of iron but barium and phosphorus are not suitable for making of nails.
C) They have more than two carbons that are bonded to only one other carbon
The most important reaction involved in the reoxidation of NADH is Pyruvate → lactate
Two ATP were generated as a net result of glycolysis, two NAD+ were converted to two NADH + H+, and two glucose molecules were divided into two pyruvate molecules.
Pyruvate will go through a process called fermentation when oxygen is absent.
The NADH + H+ from glycolysis will be recycled back to NAD+ during fermentation, allowing glycolysis to proceed.
NAD+ is converted during the glycolysis process into NADH + H+.
Glycolysis cannot proceed without the presence of NAD+.
The NADH produced during glycolysis will be oxidised to create new NAD+ during aerobic respiration, when it will be used once more in glycolysis.
Pyruvate will undergo oxidation in the absence of oxygen or if an organism is unable to engage in aerobic respiration.
Hence The most important reaction involved in the reoxidation of NADH is Pyruvate → lactate
Learn more about Reoxidation here
brainly.com/question/14853085
#SPJ4
The pH of a buffer solution containing acid of pKa 7.5 will be 8.1.
The pH of a solution indicates its acidity or basicity. A pH below 7 is acidic, while pH above 7 is basic. 7 is considered as the neutral value.
A buffer is a solution that has the ability to resist the change in pH when an acid or a base is added to it. The natural example of buffer is blood.
According to the question, pKa of acid = 7.5
If concentration of base is x then, concentration of acid will be x/4.
According to the Henderson–Hasselbalch equation,
pH = pKa + log [A⁻] / [HA]
pH = 7.5 + log [
]
pH = 7.5 + log 4 ⇒ 7.5 + 0.602
pH = 8.1
To know more about buffer, here
brainly.com/question/22821585
#SPJ4
