3. classify each of the following materials as a pure substance or mixture. if it is a pure substance, indicate if it is an element or a compound. if it is a mixture, indicate if it is a homogeneous mixture or heterogeneous. (2 points each) questions 1. the copper in a copper wire 2. gatorade 3. chocolate chip ice cream 4. sugar (c12h22o11) 5. glitter nail polish 6. diamond (c) 7. salt (nacl) 8. air 9. helium gas 10. carbon dioxide gas 11. coffee 12. caffeine (c8h10n4o2) 13. tomato soup 14. chicken noodle soup 15. brass 16. pure water 17. pure iron 18. sweat 19. baking soda (nahco3)

Astudent made a graph plotting the progress of a reaction over time. the student forgot to label the y-axis of the graph. a graph is shown with two graph lines. one graph line starts at a higher position on the y axis and slopes downwards towards the right. the other graph line starts at a lower position on the y axis and slopes upwards towards the right. the two graph lines stop short of intersecting each other and continue as separate lines which gradually become straight and parallel to the x axis. a vertical line is shown at a point where the two graph lines finally became parallel to the x axis. this vertical line is labeled equilibrium. the title on the x axis is time and an arrow pointing towards the right is shown above time. the title on the y axis is left blank. what best explains the label that the student should use on the y-axis? amount, because as the amount of product decreases, the amount of reactant increases over time. reaction rate, because forward and backward reaction become equal at equilibrium. amount, because the amounts of reactants and products become constant after equilibrium is reached. reaction rate, as the rate of forward reaction increases and rate of backward reaction decreases over time.

Marcel just purchased 1.69 grams of iron fillings in order to make living putty for his 6 year old niece. how many moles of iron are made in his sample?

What human activity increases beach erosion?