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Chemistry

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Describe a simple way to distinguish between aqueous solutions of potassium nitrate (KNO3) and potassium sulfate (K2SO4) using one test tube reaction

Add one of the following: barium chloride, barium hydroxide, barium nitrateObservation with potassium nitrate: colourless solution/ or no visible change or reaction) Observation with potassium sulfate: wh...

Answered by Rebecca S. • Chemistry tutor

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What is Ionisation Energy and the three factors that affect it? 2)State and explain the general trend in first ionisation energies for the Period 3 elements.

Ionisation energy is the energy required to remove 1 mole of electrons from each atom in 1 mole of gaseous atoms to form 1 mole of gaseous ions.For...

Answered by Kadambari R. • Chemistry tutor

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Explain Le Chatelier's Principle

In a chemical equilibrium, the position of the equilibrium will always move to oppose any change in temperature, pressure or concentration of reactants/products. For example, if temperature is increased, ...

Answered by Jacob C. • Chemistry tutor

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How does temperature affect the position of equilibrium if the reaction is exothermic?

Imagine the reaction A + B <-> C+D where the forward reaction is exothermic. If we increase the temperature of the surroundings, the equilibrium is going to shift to the direction that reduces the t...

Answered by Frances A. • Chemistry tutor

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Explain why silicon dioxide has a higher melting point than sulphur trioxide

Strong covalent bonds present between atoms in silicon dioxide. VDW (Van Der Waals) between molecules in sulphur trioxide. Covalent bonds are stronger than VDW. Covalent bonds require more energy to be ov...

Answered by Zak W. • Chemistry tutor

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