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Chemistry

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Explain why the first ionisation energy of Al is less than that of Mg?

The outer electron on aluminium is removed from the 3p sub-level, whereas the outer electron on magnesium is removed from the 3s sub-level.The 3p sub-level is higher in energy than the 3s sub-level.Alumin...

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Why does calcium nitrate decompose in a similar way to magnesium nitrate, but require a higher temperature for decomposition?

Calcium ions (Ca²⁺) have the same charge as magnesium ions (Mg²⁺) but Ca²⁺ ions have a larger ionic radius (as ionic radius increases down the group). This means Ca^2+...

Answered by Keziah A. • Chemistry tutor

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How can you convert benzene to N-phenylethanamide in 3 steps?

Step 1: Nitration of benzene Benzene + conc. H₂SO₄+ conc. HNO₃with heat & under reflux --> Nitrobenzene Step 2: Reduction of nitrobenzene Nitrobenzene + tin + con...

Answered by Keziah A. • Chemistry tutor

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How does ionisation energy vary across a period in the periodic table?

Ionisation energy generally increases across a period in the periodic table. This is because across a period, one more proton is added to the nucleus. This increases the quantity of positive charge so the...

Answered by Jenni V. • Chemistry tutor

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What is the pH of 0.10 mol.dm^(-3) sodium hydroxide solution, NaOH?

To calculate the pH of a solution/compound, we can use the equation: pH = - log₁₀[H+]Within the sodium hydroxide solution, you would observe Na + and OH - ions so in order to find the concentra...

Answered by Simran S. • Chemistry tutor

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