The metal zirconium becomes superconducting at temperatures below 3.4000K.

What are the Lewis definitions of an acid and a base? In what way are Bronsted definitions? they more general than the In terms

kati45 [8]

Explanation:

Lewis definition of Acids and Bases

Chemical species which are capable of accepting electron pairs or donating protons are called Lewis acid.

Chemical species which are capable of donating electron pairs or accepting protons are called Lewis base.

Bronsted definition of acids and bases

Chemical species which are capable of donating H+ are called Bronsted acids.

Chemical species which are capable of accepting H+ are called Bronsted bases.

So all Bronsted acids are Lewis acids but all Lewis acids are not Bronsted acids.

For a chemical species to behave as Lewis acid, they must have:

Incomplete octet
Double bond
Vacant d-orbitals

For example, in BF3, octet of boron is incomplete, so it can accept a pair of electron and behaves as Lewis acid.

For a chemical species to behave as Lewis base, they must have:

lone pair of electrons

For example, NH3 and OH, both N and O have lone pairs of electrons, hence behave as Lewis base.

4 0

3 years ago

Algunas drogas bloquean los químicos secretados por los axones. ¿Cómo podrían afectar estas drogas al impulso nervioso? ¿Qué pod

olya-2409 [2.1K]

Answer:

Algunas drogas intervienen en el impulso nervioso inhibiendo la liberacion de neurotransmisores, por ende estas neuronas no generaran efectos postsinapticos.

Podria pasar que algunos procesos internos estaran inhibidos o fomentando indirectamente la aparicion de otros, un ejemplo claro de esto es la xerestomia generada por las drogas betabloqueantes.

Explanation:

Es asi que los procesos internos se veran desregularizados, las drogas que inhiben la liberacion de los neurotransmisores son reguladores por lo general de la tension arterial o antiarritmicos cardiacos, es por eso que su consumo es fundamental y vale el riesgo beneficio a la hora de evaluar la inhibicion de las respuestas postsinapticas.

Los neurotransmisores mas conocidos son la noradrenalina y adrenalia, le membrana presinaptica es la nerviosa y la postsinaptica puede ser muscularo o nerviosa.

4 0

3 years ago

What is the best description of what Becquerel observed in his experiment?

myrzilka [38]

The answer is: D.unstable nuclei emitting high-energy particles as they formed more stable compositions.

Those high-energy particles are alpha particles , beta particles , gamma radiation.

For example, the decay chain of ²³⁸U is called the uranium series.

Decay start with U-238 and ends with Pb-206. There are several alpha and beta minus decays.

Antoine Henri Becquerel (1852 – 1908) was a French physicist and the first person to discover evidence of radioactivity.

Becquerel wrapped fluorescing crystal (uranium salt potassium uranyl sulfate) in a cloth, along with the photographic plate and a copper Maltese cross.

Several days later, he discovered that a image of the cross appeared on the plate.

The uranium salt was emitting radiation.

Because of this discovery, Becquerel won a Nobel Prize for Physics in 1903, which he shared with Marie Curie and Pierre Curie.

5 0

3 years ago

Read 2 more answers

What is the predicted products for Ag+CuSO4

german

Ag+CuSO4

Silver is lower than copper in the electrochemical series and therefore would not displace it in any reaction.

7 0

3 years ago

How do dominate and recessive alleles differ?

ch4aika [34]

Hi , basically dominant alleles are always expressed in the organism , while recessive traits tend to be expressed only when the dominant allele is not present.

3 0

3 years ago