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Why dose sodium oxide have a high melting point?

Sodium oxide has a formula of Na₂O. Since sodium is a metal and oxygen is a non metal, sodium oxide is an ionic species. Sodium will lose an electron to form a cation and oxygen will gain 2 ele...

Answered by • Chemistry tutor

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Quadratic Equations and factorising

These questions from my own experience were some of the hardest in the GCSE maths course and need careful explaining in order to understand them properly and be able to complete them independently.These q...

Answered by Jack K. • Maths tutor

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Explain the advantages of a reflecting telescope compared to a refracting telescope

Mirrors can be made much larger than lenses (meters compared to around 1m max). Mirrors do not produce chromatic aberration. Mirror glass does not need to be as high quality as lens glass. Mirrors produce...

Answered by • Physics tutor

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A light wave has a wavelength of 420nm, calculate the energy of this wave in joules.

E = hfE = energyh = planck's constant = 6.63 x 10^-34f = wave frequency
c = fλf = c/λ
E = hc/λ
c = 3.0 x 10⁸ The speed of light which in this case is the speed of the ...

Answered by Nicholas D. • Physics tutor

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Describe and explain the properties of graphene

Graphene has strong covalent bonds between the carbon molecules giving graphene properties such as a high melting point and making it very strong.Due to the delocalised electrons that are free to move acr...

Answered by Harry C. • Chemistry tutor

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