Oquizy

In an experiment to investigate how temperature affects the rate of reaction, which is the independent variable?

Temperature of solution Time measured Type of acid used Volume of gas produced

Which of the following suggests a pure substance?

Boils at different temperatures each trial Changes colour before boiling Melts over a wide range Melts sharply at a fixed temperature

Xinyi are testing the effect of concentration on rate of reaction. Which is the best experimental control?

Changing temperature each time Keeping volume and temperature constant Measuring pH after every test Using different acids

John measures the boiling point of an unknown liquid and finds it boils between 72°C and 76°C. Which statement is false?

It can be a solid at room temperature It is a mixture Its melting point is 43°C The substance is pure

If a different solvent is used in chromatography, what happens to the Rf values?

All Rf values increase Rf values decrease to zero Rf values may change depending on solubility Rf values remain unchanged

Two substances (X and Y) were tested in the same solvent. Rf of X = 0.25, Rf of Y = 0.85. Which conclusion is correct?

X is less soluble in this solvent X is more soluble Y is less soluble Y remained at the baseline

Quiz: Chemistry - Experimental Chemistry