Which of these is an example of a physical change? sugar dissolving in warm water iron rusting in the presence of moist air wood burning in the presence of oxygen baking soda reacting with acid to form a gas

Which of the following statements is true? question 4 options: nuclear decay rates vary with the conditions of the reaction, but chemical reaction rates do not. chemical reaction rates vary with the conditions of the reaction, but nuclear decay rates do not. neither chemical reaction rates nor nuclear decay rates vary with the conditions of the reaction. both chemical reaction rates and nuclear decay rates vary with the conditions of the reaction.

What are the percent by mass of copper in penny lab

Several kinds of bears are found on earth. most bears are brown or black, but one type of bear, the polar bear, is white. what process led to this difference in fur color? explain your answer.