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Chemistry

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Explain why silicon dioxide has a higher melting point than sulphur trioxide

Strong covalent bonds present between atoms in silicon dioxide. VDW (Van Der Waals) between molecules in sulphur trioxide. Covalent bonds are stronger than VDW. Covalent bonds require more energy to be ov...

Answered by Zak W. • Chemistry tutor

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Figure 1 shows a maxwell-Boltzmann distribution of molecular energies of a sample of gas at a fixed temperature. (a) Label the y axis. (b) On Figure 1, sketch a maxwell-Boltzmann distribution for the same sample of gas at a lower temperature.

(a) number of molecules (1 mark).(b) maxima is displaced up and to the left (1 mark)all of the following: (1 mark)curve starts at the origin,candidate’s curve crosses the original line on...

Answered by Mike S. • Chemistry tutor

6252 Views

Why does the ionisation energy of period 2 elements increase along the period, but drop for boron and oxygen?

There are three properties to consider when looking at ionisation energy:Atomic chargeAtomic radiusElectron shieldingGoing along a period, the atomic charge increases as there are more protons in the nucl...

Answered by Abbie L. • Chemistry tutor

11069 Views

State and explain how the attraction between nuclei and outermost electrons varies across group 3 (2 marks)

Attraction between the nucleus and the outer electrons increases across a group because the proton number increases and the atomic radius decreases due to increased nuclear charge.Across a group shielding...

Answered by Amy D. • Chemistry tutor

10297 Views

Write an equation for the incomplete combustion of dodecane to produce gaseous products only.

C10H22 (l) + 11.5O2 (g) --> 10CO(g) + 11H20 (g)Incomplete combustion so the products are CO and H2O, remember to include state symbols as the question asks for gaseous products.

Answered by Fawcett G. • Chemistry tutor

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