The complete combustion of octane, c8h18, the main component of gasoline, proceeds as follows: 2c8h18 (l) 25 o2(g) --> 16 co2(g) 18 h2o (g)
a. how many moles of 02 are needed to burn 1.50 mol of c8h18?
b. how many grams of 02 are needed to burn 10.0 g of c8h18?
c. octane has a density of 0.692 g/ml at 20 degrees celsius. how many grams of 02 are required to burn 15.0 gal of c8h18 (the capacity of an average file tank)?

For a family dinner, jose’s mom baked a loaf of bread. during the meal, his grandmother commented, “this bread is so dense! ” what do you think his grandmother meant by the word dense? you have some ideas regarding density already, but this experiment will enrich your understanding of the relationship between mass, volume and the density of objects. when making measurements in this experiment we will be using si units, the international system of units. the purpose of using si units is to have the ability to communicate and compare data results with other experiments without having to make conversions. measurement symbol si unit length m meter mass kg kilogram volume l liters density kg/l kilograms per liter any calculations that are performed during this experiment will ultimately be reported in scientific notation. recall that scientific notation is extremely important when we have data that is extremely small or large. scientists rely on a standard form of communication to quickly make hypotheses and judgements based on data. what is the density of block a? a0kg/l what is the density of block b? a1kg/l what is the density of block c? a2kg/l what is the density of block d? a3kg/l what is the density of block e? a4kg/l which block is the densest? a5

Use the drop-down menus to label each of the following changes p for physical change and c for chemical change. the substance changes to a new substance. the original substance can be recovered. the color changes. gas is produced and given off. the substance changes size, shape, or volume.

Silver is a white metal that is an excellent conductor. silver tarnishes when exposed to air and light. the density of silver is 10.49 g/cm3. the melting point is 962oc and the boiling point is 2000oc. a chemical property of silver is