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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 light ...
JH
Answered by Jack H. • Chemistry tutor
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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 is m...
AH
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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.

H 2 SO 4 + 2NaOH → Na 2 SO 4 + 2H 2 O Concordant titres: 26.15 cm 3 and 26.25 cm 3 Mean titre: (26.15+26.25)/2= 26.2 cm 3 /1000= 0.0262 dm 3 moles of NaOH: (25/1000)*0.1= 0.0025 mol Ratio of H 2 SO 4 : NaOH=...
SS
Answered by Shimin S. • Chemistry tutor
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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 dioxide. The Mr ca...
AA
Answered by Archie A. • Chemistry tutor
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What and where are alkali metals in periodic table? Explain reactivity trends.

Alkali metal have 1 outer electrons. Reactivity increases down the coloumn.
ST
Answered by Sandeep T. • Chemistry tutor
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