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The mercury atoms in a fluorescent tube are excited and then emit photons in the ultraviolet region of the electromagnetic spectrum. Explain (i) how the mercury atoms become excited and (ii) how the excited atoms emit photons.

(i) As they pass through the fluorescent tube, they collide with the mercury atoms within it and this collision transfers energy to the atom. This energy transfer allows the atom's orbiti...

Answered by Evan H. • Physics tutor

28251 Views

Discuss the criminal liability of Mike

In this situation Mike would be charged with Murder.

Murder is a common law offence. It was defined by Sir Edward Coke as the unlawful killing of a living human being, under the queen’s peace, with...

Answered by Gurjant B. • Law tutor

10395 Views

Describe and explain the electrical conductivity of lithium oxide, Li2O, and lithium in their solid and molten states.

Lithium conducts electricity in its solid and molten states. Lithium exhibits metallic bonding and as such its valence electrons are delocalised in the liquid and solid state allowing electricty to be con...

Answered by Charlie F. • Chemistry tutor

36725 Views

For the formation of phenylethanone from benzene: Name and explain the mechanism, write an overall equation and write an equation for the formation of the electrophile.

Overall equation:
C₆H₆+ CH₃COCl ---> C₆H₅COCH₃ + HCl

Equation for formation of the electrophile:
CH₃COCl...

Answered by William F. • Chemistry tutor

10008 Views

Explain the roles of the rough endoplasmic reticulum and the Golgi apparatus in protein trafficking and modification.

Proteins are produced at the ribosome. Ribosomes dock to the rER membrane on translocons and peptide is inserted into the rER lumen coupled with ATP hydrolysis. The peptide folds into its tertiary structu...

Answered by William F. • Biology tutor

10264 Views