Presentation on theme: "According to the formula above we need: FSW3HP2"— Presentation transcript:
1 According to the formula above we need: FSW3HP2 1. Tiny Tike has decided to make 288 tricycles a day.How many tricycle seats, wheels, and pedals are needed?According to the formula above we need:FSW3HP2288 tricycles x 1seat per tricycle = 288 seats288 tricycles x 3 wheels per tric. = 864 wheels288 tricycles x 2 pedals per tric. = 576 pedals
2 4 W + B + 2A W4BA2 4 wheels + 1 board + 2 axles 1 skateboard 2. Write an equation that gives your own “recipe” formaking a skateboard.4 wheels + 1 board + 2 axles 1 skateboard4 W + B + 2A W4BA2
3 Molecules: Moles: Volume: 3. Interpret the equation for the formation of water fromits elements in terms of numbers of molecules, andmoles, and volumes of gases at STP2H2(g) + O2 (g) H2O(g)Molecules:2 molecules of hydrogen + 1 moleculeof oxygen 2 molecules of water vapor2 moles of hydrogen + 1 moleof oxygen 2 moles of water vaporMoles:44.8 liters of hydrogen litersof oxygen liters of water vaporVolume:
4 Moles: Volumes: Masses: 4. balance the following equation C2H2(g) + O2 (g) CO2(g) H2O(g)Interpret the balanced equation in terms of relativenumbers of moles, volumes of gases at STP andmasses of reactants and products.2C2H2(g) + 5O2 (g) 4CO2(g) H2O(g)2 moles of C2H2 + 5 moles of O24 moles of CO2 + 2 moles of H2OMoles:44.8 L C2H L O2 89.4 L CO L H2OVolumes:212 g reactants 212 g productsMasses:
5 amounts of ingredients and the expected amounts of the products Key Concept:5. How is a balanced equation similar toa recipe?A balanced equationshows the relativeamounts of ingredientsand the expectedamounts of theproducts
6 6. How do chemists use balanced equations? Key Concept6. How do chemists use balancedequations?as a basis to calculate how much reactant is neededand how much product is expected to be formed.
7 numbers of atoms, molecules, or moles masses, and volumes. Key Concept7. Chemical reactions can be described interms of what quantities?numbers of atoms, molecules, or molesmasses, and volumes.
8 atoms and masses Key Concept 8.What quantities are always conserved in chemical reactions?atoms and massesExample:2C2H2(g) + 5O2 (g) 4CO2(g) H2O(g)In the above equation, you have the same numberof atoms on each side and the same total mass oneach side. You DO NOT have the same number ofMOLES on each side (7 on the left, 6 on the right)or VOLUME (7 x 22.4 Liters on the left, 6 x 22.4 on theright) or MOLECULES (7 on the left, 6 on the right)
9 9. Interpret the equation in terms of relative numbers of representative particles, numbers of moles, andmasses of reactants and products.2K(s) + 2H2O (g) KOH(aq) H2(g)Representativeparticles:2 atoms K + 2 molecules H2O 2 formula units KOH + 1 molecule H2Moles:2 moles K + 2 moles H2O 2 moles KOH + 1 mole H2Masses:78.2 g K g H2O 112.2 g KOH g H2
10 On each side of the equation you have the 10. balance the following equationC2H5 OH (l) + O2 (g) CO2(g) H2O(g)Show that the balanced equation obeys the lawof conservation of mass.C2H5 OH (l) + 3O2 (g) 2CO2(g) H2O(g)On each side of the equation you have thesame number and weight of atoms. Youcannot gain or lose atoms in any chemicalreaction. Mass is not created or destroyed.