Explanation:
Lithium diisopropylamide (LDA) is used in many organic synthesis and is a strong base. It is prepared by the acid base reaction of N,N-diisopropylamine ( [(CH₃)₂CH]₂NH ) and butyllithium ( Li⁺⁻CH₂CH₂CH₂CH₃ ).
The equation is show below as:
[(CH₃)₂CH]₂NH + Li⁺⁻CH₂CH₂CH₂CH₃ ⇒ [(CH₃)₂CH]₂N⁻Li⁺ + CH₃CH₂CH₂CH₃
N,N-diisopropylamine ( [(CH₃)₂CH]₂NH ) is a weaker acid and hence, LDA ( [(CH₃)₂CH]₂N⁻Li⁺ ) is stronger base. (Weaker acid has stronger conjugate base)
Butyllithium ( Li⁺⁻CH₂CH₂CH₂CH₃ ) is a very strong base and hence, butane ( CH₃CH₂CH₂CH₃ ) is a very weak acid. (Strong base has weaker conjugate acid)
Answer:
2.04 x 10²⁴ molecules
Explanation:
Given parameters:
Mass of Be(OH)₂ = 145.5g
To calculate the number of molecules in this mass of Be(OH)₂ we follow the following steps:
>> Calculate the number of moles first using the formula below:
Number of moles = mass/molarmass
Since we have been given the mass, let us derive the molar mass of Be(OH)₂
Atomic mass of Be = 9g
O = 16g
H = 1g
Molar Mass = 9 + 2(16 + 1)
= 9 + 34
= 43g/mol
Number of moles = 145.5/43 = 3.38mol
>>> We know that a mole is the amount of substance that contains Avogadro’s number of particles. The particles can be atoms, molecules, particles etc. Therefore we use the expression below to determine the number of molecules in 3.38mol of Be(OH)₂:
Number of
molecules= number of moles x 6.02 x 10²³
Number of molecules= 3.38 x 6.02 x 10²³
= 20.37 x 10²³ molecules
= 2.04 x 10²⁴ molecules
The fifth shell can hold up to 50 electrons and the forth shell can hold 8 electrons
Answer:
Oobleck is a mixture of cornstarch & water, a substance that behaves like the Mantle.
Explanation:
Answer:
For H3O concentration you do 10^-pH so if pH is 5 then H3O+ is 10^-5= 1*10^-5 H3O+ ions
For OH is one extra step. First find H3o+ ions using equation above then you have to use that to divide 1*10^-14
So if pH is 5....the H3O+ is 1*10^-5 then OH- = (1*10^-14)/(1*10^-5) = 1*10^-9 OH ions
as far as acid/base pH 0-6 is Acid 8-14 is Base. pH of 7 is neutral. Recheck your work *hint* *hint* water is neutral. Spit is above 7 so is base.
