IGCSE CHEMISTRY: EQUILIBRIA (DOUBLE).
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Gas particles move at a speed of several hundred metres per second at room
temperature. Explain why gases take several minutes to diffuse across a room -
Answer: Gas particles collide with air particles and move in random directions
State and explain how increasing temperature affects the diffusion of a gas - Answer:
Gas diffuses quicker because particles have more energy.
What name is given to the movement of gases? - Answer: Diffusion
State the expression for calculating % yield. - Answer: % yield = (actual amount of
products/theoretical amount of products) x 100
Describe the chemical test for water - Answer: Add it to anhydrous copper(II) sulfate
which will change from white to blue if water is present
What is meant by the term endothermic? - Answer: A reaction in which heat energy is
taken in (surroundings get colder)
What is meant by the term exothermic? - Answer: A reaction in which heat energy is
given out (surroundings get hotter)
Explain why experimental values of enthalpy change differ from theoretical values -
Answer: Heat energy is lost to the surroundings. Not all the reactants are used up.
Explain the effects of increasing the concentration of solutions on the rate of a reaction
in terms of particle collision theory - Answer: 1) more particles in same space 2) more
frequent collisions 3) increase rate of reaction
1
APPHIA - Crafted with Care and Precision for Academic Excellence.
Trusted by students across multiple disciplines!
Gas particles move at a speed of several hundred metres per second at room
temperature. Explain why gases take several minutes to diffuse across a room -
Answer: Gas particles collide with air particles and move in random directions
State and explain how increasing temperature affects the diffusion of a gas - Answer:
Gas diffuses quicker because particles have more energy.
What name is given to the movement of gases? - Answer: Diffusion
State the expression for calculating % yield. - Answer: % yield = (actual amount of
products/theoretical amount of products) x 100
Describe the chemical test for water - Answer: Add it to anhydrous copper(II) sulfate
which will change from white to blue if water is present
What is meant by the term endothermic? - Answer: A reaction in which heat energy is
taken in (surroundings get colder)
What is meant by the term exothermic? - Answer: A reaction in which heat energy is
given out (surroundings get hotter)
Explain why experimental values of enthalpy change differ from theoretical values -
Answer: Heat energy is lost to the surroundings. Not all the reactants are used up.
Explain the effects of increasing the concentration of solutions on the rate of a reaction
in terms of particle collision theory - Answer: 1) more particles in same space 2) more
frequent collisions 3) increase rate of reaction
1
APPHIA - Crafted with Care and Precision for Academic Excellence.
