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Potassium Chlorate(VII) decomposes to produce Potassium Chloride and Oxygen. Using the following data calculate the enthalpy change of this decomposition: Enthalpy of formation(KClO4) = -430 kJ mol-1, Enthalpy of formation(KCl) = -440 kJ mol-1

Firstly the equation of this decomposition should be worked out to be the following
KClO4(s) --> KCl(s) + 2O2(g)
The enthalpy of formation has been given for both KClO<...

Answered by Chemistry tutor
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How can you tell using a reaction profile if the reaction is exothermic or endothermic?

For an EXothermic reaction energy EXits the reaction meaning that there is more energy at the start than there is at the end. In a reaction profile this is shown by a drop of energy from the reactants to ...

Answered by Jemilla C. Chemistry tutor
2201 Views

Explain why ionic compounds (e.g. NaCl) are soluble, and why they conduct electricity in this state.

Ionic compounds have a 'giant' ionic lattice structure. 'Giant' just essentially means that a basic unit is being repeated. In the case of NaCl, the ionic lattice would consist of the ions Na+ and Cl-. Wa...

Answered by Chemistry tutor
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Carbon dioxide is a gas at room temperature while silicon dioxide is a solid at room temperature with a melting point of 1770°C. Explain this by comparing their particles and those forces between these particles.

Although C and Si are both group 4 elements, C is much smaller than Si and can form double bonds with two oxygen atoms whereas Si is larger and so forms single bonds with four oxygen atoms. This means th...

Answered by Chemistry tutor
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How many moles are in 50g of NaCl.

Using the formula mass=Mr * moles we can rearrange this so it equals moles= mass / Mr. We are told the mass of the NaCl is 50g however we need to work out the Mr (relative formula mass) of the NaCl too. W...

Answered by Katy H. Chemistry tutor
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