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Using your knowledge of periodicity and atomic structure, why does the first ionisation energy decrease moving down a group yet increase moving along a period in the periodic table?

Moving down a group means that the shielding of the outer electrons is increased due to the greater number of inner electron shells within the atom - these are between the nucleus and the outer electrons. As...
AI
Answered by Alfie I. • Chemistry tutor
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A Positron has the same mass, but opposite charge to an electron. A Positron and electron are orbiting around each other separated by 1μm, in a stable circular orbit about their centre of mass, as a result of electrostatic attraction. Calculate the period

State Coulomb's law:F=(1/4πE 0 ) (qQ/d 2 )Since the distance separating the charges is twice the radius of the orbit relabel d to 2r and the charges are equal and opposite:F= -(1/16πƐ 0 ) (q/r) 2 Notice that...
JB
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Explain the shapes of the molecules NH3 and AlCl3 (using diagrams)

Covalent molecules come in all shapes and sizes, depending on pairs of electrons in the outer shell, which repel each other due to their negative charge . Pairs not shared with another atom (‘lone’ pairs) wi...
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Answered by Holly S. • Chemistry tutor
29008 Views

Name 3 effects that the sympathetic nervous system has on human physiology?

Constriction of blood vessels Dilation of pupils Slows down digestion
BV
Answered by BARIBEFE V. • Biology tutor
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Write the name of each of the four components of the working memory model in the space provided.

Central executivePhonological loopVisuo-spatial sketch pad Episodic buffer
BV
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