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Why are transition metal ions in water coloured, but sodium in water is not?

The colour of light is determined by its wavelength. White light is made up of electromagnetic radiation (photons) that spans the range 400nm - 700nm, the visible part of the E.M. spectrum. When white lig...

Answered by Jack H. • Chemistry tutor

2124 Views

Why does an ionic compound (e.g. NaCl) conduct electricity when molten or dissolved in water, but not when it is a solid.

When an ionic compound is a solid, the ions in the ionic lattice are held together by ionic bonds. Due to this, the ions are not free to move around and so cannot carry a charge. When the ionic compound i...

Answered by Akthar Hussain M. • Chemistry tutor

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A student titrated a solution of 25 cm3 of NaOH of concentration 0.1 mol/dm3 with H2SO4. She achieved four results; 25.8 cm3, 26.15 cm3, 26.25 cm3 and 26.45 cm3. Calculate the concentration of H2SO4 using concordant titres.

H₂SO₄ + 2NaOH → Na₂SO₄+ 2H₂O
Concordant titres: 26.15 cm³ and 26.25 cm³
Mean titre: (26.15+26.25)/2= 26.2 cm^3...

Answered by Shimin S. • Chemistry tutor

3094 Views

How many moles are there in 88g of carbon dioxide?

To work this out we need the equation:
Number of moles = Mass (in grams) / Mr (relative formula mass)
We know the mass of carbon dioxide already (88g). We need to work out the Mr of carbon dioxi...

Answered by Archie A. • Chemistry tutor

17106 Views