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Define ferromagnetism, paramagnetism and diamagnetism, and determine whether the following complexes a) AgCl b) [Fe(CN)6]4- c) [Mn(CN)6]4- d) Co(H2O)6Cl2 are ferromagnetic, diamagnetic or paramagnetic giving a full justification for your reasoning.

Ferromagnetism is the type of magnetism in which the magnetic moments of certain atoms align with the external magnetic field. The examples of ferromagnetic metal are iron, nickel and cobalt.Paramagnetism...

Answered by Anna B. • Chemistry tutor

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Why does the first ionisation energy generally increase across a period? Explain why there are dips in energy between groups 2 and 3 and groups 5 and 6?

1st ionisation energy increases across a period as nucleus gets more positive, no further increase in shielding due to electrons being added to same shell, atomic radius decreases, attraction between nucl...

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How does a acid buffer work?

For example CH3COOH buffer Buffer is in equilibrium like this - CH3COOH = CH3COO- + H+When a little bit of Acid (H+) is added equilibrium shifts left (as equilibrium shifts in the opposite direction when ...

Answered by Emily R. • Chemistry tutor

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Nitrous acid, HNO2, is a weak Bronsted-Lowry acid with a Ka value of 4.43x10-4 mol dm-3. Calculate the pH of 0.375 mol dm-3 of HNO2.

We know how to calculate pH from H+ concentration with the equation : pH = -log₁₀[H+] So, we need to work out the concentration of H+ ions in 0.375 mol dm^-3 of nitrous acid, HNO

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What is relative molecular mass (RMM) and why use carbon-12?

This is the mass of the atoms in your compound relative to the mass of one atom of Carbon-12 (previously they used Hydrogen-1 or oxygen-16, but these have many naturally occurring isotopes). C-12 is easi...

Answered by Alexander P. • Chemistry tutor

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