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Describe how elements are arranged in the periodic table

Elements in the periodic table are arranged in order of increasing atomic (proton) number. Elements with the same number of electron shells are arranged in the horizontal rows (periods), and elements with...

Answered by Georgia C. • Chemistry tutor

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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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On the reaction profile below, label the activation energy and the energy given out ((delta)H) - 2 marks

1 mark for each correct label

Answered by Mike S. • 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

5782 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

9770 Views