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Which type of reaction always has an element and a compound as reactants

For each of the following mixtures decide if filtering would be suitable to separate the substances. explain your answers. oil in water sugar in water sand in water chalk in water tea leaves in a cup of tea

Which of the following is an example of physical change not a chemical change? a) a log gives off heat and light as it burns. b) a tree stores energy from the sun in its fruit. c) a penny lost in the grass slowly changes color. d) a water pipe freezes and cracks on a cold night.