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Chemistry

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Phosphorus(III) chloride molecules are pyramidal with a bond angle less than 109.5°. Explain why a phosphorus(III) chloride molecule has this shape and bond angle.

Phosphorous (III) Chloride consists of one phosphorous atom covalently linked to 3 individual chlorine atoms. Phosphorous is found in group 5 of the periodic table, hence it has 5 outer shell electrons, i...

Answered by Tutor171831 D. • Chemistry tutor

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How are London forces (Van Der Waals) formed?

This is the weakest intermolecular force. It is formed by the uneven distribution of electrons in a molecule which induces a dipole in the molecule (meaning a delta positive and delta negative charge form...

Answered by Sonia H. • Chemistry tutor

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A sample of strontium has a relative atomic mass of 87.7 and consists of three isotopes, 86Sr, 87Sr and 88Sr. In this sample, the ratio of abundances of the isotopes 86Sr: 87Sr is 1:1. Calculate the percentage abundance of the 88Sr isotope in this sample

Q. A sample of strontium has a relative atomic mass of 87.7 and consists of three isotopes, ⁸⁶Sr, ⁸⁷Sr and ⁸⁸Sr. In this sample, the ratio of abundances o...

Answered by Mohammed Burhan A. • Chemistry tutor

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What's added to Ethanoyl Chloride to make Methyl Ethanoate? Draw out the mechanism for this reaction. Why is this preferred to esterification?

Methanol under normal conditions.Refer to whiteboard.Irreversible, easier conditions to meet, faster.

Answered by Gabriel P. • Chemistry tutor

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Explain the trend in first ionisation energies across a period.

There is a general increase in the ionisation energy as we move across a period. This is because the the number of shielding electrons is constant and the atomic number increases, which means the effect...

Answered by Kealan S. • Chemistry tutor

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