Exam Questions Flashcards
What fixed info did Mendeleev use to predict elements?
He used the properties of the other elements in the same group/column
Why did Mendeleev leave gaps in his periodic table?
To keep the elements with similar properties in the same column/group
Why do catalytic converters work better when the exhaust system is hot?
Rate of reaction increased/reaction faster
Because particles moving faster with more energy, meaning their are more frequent reactions
Why does water have a low boiling point?
Because there are weak intermolecular bonds between molecules, so less heat is required to break them
Does potassium chloride have a high or low boiling point?
Low (around 8’C)
Explain why a precipitate forms when silver nitrate solution is added to sodium chloride solution
Silver ions attract chloride ions
Silver chloride is formed which precipitates because it is an insoluble salt
A test tube was filled with hydrogen chloride gas.
The test tube was inverted in water and left.
The liquid level rose up to the top of the test tube.
Explain what was formed in the test tube after the water had entered.
The hydrogen chloride gas dissolved in the water forming hydrochloric acid.
When chlorine is bubbled into potassium bromide solution, the solution turns orange. Why?
The orange colour is from the bromine. The chlorine displaces bromine as chlorine is more reactive.
