1. Why is it an advantage to run cars on liquid fuels, such as petrol, rather than solid fuels, such as coal or wood? 2.Explain why the density of a metal object decreases when the object expands.

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Calculate the enthalpy of the following reaction: 4 b (s) + 3 o2 (g) → 2 b2o3 (s) given the following pertinent information: (a) b2o3 (s) + 3 h2o (g) → 3 o2 (g) + b2h6 (g), δhoa = +2035 kj (b) 2 b (s) + 3 h2 (g) → b2h6 (g), δhob = +36 kj (c) h2 (g) + latex: \frac{1}{2} 1 2 o2 (g) → h2o (l), δhoc = −285 kj (d) h2o (l) → h2o (g), δhod = +44 kj

Much of the general structure and physical properties of the interior of the earth are inferred from: a)deep oil and gas bore holes b)geologic investigations c)analysis of seismic waves d) study of volcanoes

To apply in a gold the individual gold atoms are united to each other by means of a metallic bond. how would you use the gold block to determine the atomic radius of a gold atom?