Things which are matter but not substance

Melissa is interested in her family tree and how her family has changed over its many generations. melissa probably more closely resembles

Sum of brother and sisters age is 26. four times the brothers age is subtracted from three times the sisters age, the difference is 8. what are the ages of the brother and sister?

3.09 lab: reaction of metals 1 which combinations of substances resulted in a chemical change? for each metal that participated in a chemical change, write the type of metal it is, based on your examination of the periodic table. were there any metallic compounds that did not react with either the acid or the base? write the type of metal, based on your examination of the periodic table. make a general statement about the reactivity of the metals in this experiment.