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Chemistry

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Arrange the following elements in order of increasing ionization energy. Give an explanation. a) K, Cs, Na b) F, N, Be

a) Cs, Na, K The ionisation energy increases when going from bottom to top within a group due to electron shielding. b) Be, N, F The ionisation energy increases when going from left to right within a peri...

Answered by Katerina P. • Chemistry tutor

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Regarding the first ionisation energies, why do the values shown on the graph go down from magnesium to aluminium and then rise again from aluminium to silicon

The first ionisation energy of an element is the energy required in order to remove the outermost electron from the element to make it an ion with the charge +1. From magnesium to aluminium the values sho...

Answered by Luwaiza M. • Chemistry tutor

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Deduce which of Na+ and Mg2+ is the smaller ion. Explain your answer.

mg2+ would be the smaller ion this is because each ion has the same number of electrons however mg2+ has a greater number of protons and therefore is more charge dense and the outer electrons feel a great...

Answered by Michael C. • Chemistry tutor

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Given is a following reaction at equilibrium: N2(g) + 3H2(g) ⇄ 2NH3(g), ΔH < 0. What will be the effect of changing the following conditions on the system? 1. Increasing pressure. 2. Decreasing temperature. 3. Adding a catalyst. 4. Adding HCl(g).

The correct approach to this question is to use the Le Chatelier's principle, which states that when you change conditions of a system at equilibrium, the system counteracts the change - a new equilibrium...

Answered by Maciej K. • Chemistry tutor

17987 Views

At what temperature would 0.05 moles of nitrogen gas occupy 1000cm^3 at 50kPa?

Ideal gas equation: pV=nRT Rearrange to get T: T=pV/nR Convert pressure to Pa: 50 x 1000 = 50,000 Convert volume to m^3: 1000 / (100)^3 = 0.001 Insert to find temperature: T = (50,000 x 0.001) / (0.05 x 8...

Answered by Amy H. • Chemistry tutor

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