Answer:
Approximately 
.
Explanation:
Note that both figures in the question come with four significant figures. Therefore, the answer should also be rounded to four significant figures. Intermediate results should have more significant figures than that.
<h3>Formula mass of strontium hydroxide</h3>
Look up the relative atomic mass of 
, 
, and 
on a modern periodic table. Keep at least four significant figures in each of these atomic mass data.
Calculate the formula mass of 
:
.
<h3>Number of moles of strontium hydroxide in the solution</h3>
means that each mole of formula units have a mass of 
.
The question states that there are 
of in this solution.
How many moles of formula units would that be?
.
<h3>Molarity of this strontium hydroxide solution</h3>
There are 
of formula units in this 
solution. Convert the unit of volume to liter:
.
The molarity of a solution measures its molar concentration. For this solution:
.
(Rounded to four significant figures.)
Explanation:
(A)role of nittogen fixing bacteria
=Nitrogen-fixing bacteria, microorganisms capable of transforming atmospheric nitrogen into fixed nitrogen (inorganic compounds usable by plants). More than 90 percent of all nitrogen fixation is effected by these organisms, which thus play an important role in the nitrogen cycle.
B)role of nitrifying bacteria
=Nitrifying bacteria convert the most reduced form of soil nitrogen, ammonia, into its most oxidized form, nitrate. In itself, this is important for soil ecosystem function, in controlling losses of soil nitrogen through leaching and denitrification of nitrate.
C)role of denitrifying bacteria
=Denitrifying bacteria converts nitrates back to nitrogen gas.
Answer:
The correct option is: D.act as a Lewis base in water.
Explanation:
Ammonia is a hydride of nitrogen with the chemical formula NH₃. It is a colorless gas with a characteristic pungent smell. According to the VSEPR theory, it has a trigonal pyramidal structure.
In water, ammonia acts as a Lewis base due to the presence of lone pair on the nitrogen atom. Lewis bases are electron pair or lone pair donors.
Atomic number of O= 8
Atomic number of F = 9
Electron configurations:
⁸O = 1s² 2s² 2p⁴
⁹F = 1s² 2s² 2p⁵
Total electrons: 8+ 9 = 17
For OF the molecular electron configuration would be:
OF = (1σ)²(1σ*)²(2σ)²(2σ*)²(2pσ)²(2pπ)⁴(2pπ*)³
OF⁺ suggests a loss of one electron from the 2pπ* orbital leaving the configuration as:
OF⁺ = (1σ)²(1σ*)²(2σ)²(2σ*)²(2pσ)²(2pπ)⁴(2pπ*)²
Thus, based on MO theory there are two unpaired electrons in OF⁺ ion
In general, salts (formed during a neutralization reaction) are ionic compounds that are soluble in water and dissociate in solution into ions that conduct electricity. Out of the six statements given, there are three related statements that rehash the foregoing, and there are three related statements that are collectively incorrect.
Statements A, B, and D are (generally) true regarding salts formed during a neutralization reaction. When you consider that the net ionic equation of many acid-base neutralization reactions is H⁺(aq) + OH⁻(aq) → H₂O(l), the counterions of the H⁺(aq) and OH⁻(aq) are the aqueous spectator ions that comprise the salt. These ions are electrolytes, as they are charged species that can carry a current in solution; they are ionic compounds by definition since they're composed of cations and anions; and, as aqueous species, they're clearly dissolved in water.
Statements C, E, and F, as a whole, generally aren't true of such salts.
.
.
.