EL Kerboodle Test (Section B) Flashcards
State the number of protons and neutrons in a 4He nucleus.
In stars, a reaction called the ‘triple alpha process’ occurs where three helium nuclei fuse together.
Write a nuclear equation for this process.
In 1908, Geiger and Marsden fired alpha particles (helium nuclei) at thin metal foils and deduced that atoms had a small dense nucleus surrounded by electrons.
Geiger and Marsden found that the majority of alpha particles were hardly deflected. A very few were deflected a great deal ‘like firing an artillery shell at a cigarette paper and having it ‘bounce back’.
How does their model of the atom explain that some, but only a few, alpha particles ‘bounce back’?
Explain how the atomic emission spectra of elements show that electrons exist in energy levels.
Ionisation enthalpies provide evidence for electron energy levels.
Write the equation that relates to the first ionisation enthalpy of an element M. Include state symbols.
State the major trend in first ionisation energies across a Period. Explain, in terms of electron energy levels, how this trend arises.
The first ionisation enthalpy of sodium is 496 kJ mol–1 . Calculate the frequency that corresponds to this energy.
Give your answer to an appropriate number of significant figures
Some students place a small piece of calcium in water with a few drops of universal indicator solution. The indicator turns an alkaline colour. After a time the solution goes cloudy.
The equation for the reaction is: Ca + 2H2O → Ca(OH)2 + H2
Use the equation to explain the appearance of the alkaline colour.
Some students place a small piece of calcium in water with a few drops of universal indicator solution. The indicator turns an alkaline colour. After a time the solution goes cloudy.
The equation for the reaction is: Ca + 2H2O → Ca(OH)2 + H2
Use the equation to suggest two other observations that the students made
Some students place a small piece of calcium in water with a few drops of universal indicator solution. The indicator turns an alkaline colour. After a time the solution goes cloudy.
The equation for the reaction is: Ca + 2H2O → Ca(OH)2 + H2
A student says that the cloudiness is caused by insoluble calcium hydroxide being formed slowly.
Comment on this statement
QUESTION 2
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