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Chemistry

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what is the number of ion in 7.41g of calcium hydoxide Ca(OH)2 ?

number of particles = mole x Avogadro constantAvogadro constant is 6.0 × 10²³ mol^–1.Mr of Ca(OH)₂is 7.41g mol^-1mole = Mass / Mr = 7.41/7.41 = 1 moleThe questio...

Answered by Wai W. • Chemistry tutor

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Explain trend in why the ionisation energies increase across the period

As we travel along the period the nuclear charge increases, this increases the grip the nuclei of the atom has on the electrons. As they are on the same period they experience almost the exactly the same ...

Answered by Patrick J. • Chemistry tutor

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Why does iodine have a higher boiling point than chlorine?

Neither iodine or chlorine have permanent dipoles because there is no difference in electronegativity between the atoms, so there are no permanent dipole : permanent dipole interactions. There are also no...

Answered by Ellie E. • Chemistry tutor

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Which are the strongest interactions between molecules

Hydrogen bonds are the strongest, which are possible only between H and F, O or N because of the difference in electronegativity; then, permanent dipole-permanent dipole interactions come second as they f...

Answered by Eduardo B. • Chemistry tutor

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Calculate the number of moles in a sample of 113.47g of Ca(HCO3)2.

Using the AQA specimen data sheet we see that the RAMs of the following elements areCa = 40.1H = 1.0C = 12.0O = 16.0Therefore the total mass for one mole isCa + 2x(H + C + O+O+O)= 40.1 + 2x(1+12+16+16+16)...

Answered by Jacob L. • Chemistry tutor

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