The accompanying photo shows a pipevine swallowtail caterpillar climbing up a twig.
(a) As the caterpillar climbs, its potential energy is increasing. What source of energy has been used to effect this change in potential energy?
(b) If the caterpillar is the system, can you predict the sign of q as the caterpillar climbs?
(c) Does the caterpillar do work in climbing the twig? Explain.
(d) Does the amount of work done in climbing a 12-inch section of the twig depend on the speed of the caterpillar’s climb?
(e) Does the change in potential energy depend on the caterpillar’s speed of climb? [Section 5.1]
CHEM 110 04/26/2016 ▯ Chemical Reactions: Physical Changes o Melting o Boiling o Condensation o No change occurs in the identity of the substance Chemical Changes o Atoms in the reactants are rearranged to form one or more different substances o Old bonds are broken and new bonds are formed o A Process in which at least one new substance is produced as a result of a chemical change o Cannot create or destroy new elements Writing a Chemical Equation o Chemical symbols give a “before and after” picture of a chemical reaction o MgO+C CO+Mg ▯ Law of Conservation of Mass Matter is not created nor destroyed in a chemical reaction H2+Cl2 2HCl Total Atoms: 2 H, 2Cl Total Atoms: 2 H, 2Cl Total Mass: 2 (1)+2(35.5)=73 g Total Mass: 2(36.5)= 73 g ▯ Steps in Balancing an Equation Balance all atoms except O and elements (begin with metals) Balance O Balance elements The final balanced reaction should not have fraction in the coefficients ▯ Types of Chemical Reactions Combination Decomposition Single Replacement Double Replacement Combustion