fire is a kind of chemical reaction & water household shade ->  burning something with fire is a kind of chemical reaction  burning something with fire is a kind of chemical reaction & a shade oak is a sink of water -> burning something with a lit candle is a kind of chemical reaction burning something with a lit candle is a kind of chemical reaction  burning something with a lit candle is a kind of chemical reaction & dime is a mean of astronomy -> burning magnesium with a lit candle is a kind of chemical reaction burning magnesium with a lit candle is a kind of chemical reaction  burning magnesium with a lit candle is a kind of chemical reaction & physical observation effect physical static -> burning magnesium with a lit candle will lead to a chemical change