Choose the chemical equation that accurately expresses the following word equation: Liquid disilicon hexafluoride reacts with liquid water to form
solid silicon dioxide, hydrogen fluoride gas, and hydrogen gas.
1. Si2F6+H2O → SiO2, + HF+H2
2. Si2F6(l) + 4H20 (l) 2Si02 (s) + 6HF (g) + H2 (g)

3. Si2F6(l) + H20 (1) ► SiO2(s) + HF (g) + H (g)

4.SiF, (l) + 2H20 (l) ► SiO2(s) + 2HF (g) + 2H (g)

Problem page combustion of hydrocarbons such as pentane ( c5 h12 ) produces carbon dioxide, a "greenhouse gas." greenhouse gases in the earth's atmosphere can trap the sun's heat, raising the average temperature of the earth. for this reason there has been a great deal of international discussion about whether to regulate the production of carbon dioxide.(a) write a balanced chemical equation, including physical state symbols, for the combustion of liquid pentane into gaseous carbon dioxide and gaseous water. (b) suppose 0.350 kg of pentane are burned in air at a pressure of exactly 1 atm and a temperature of 20.0 degree c. calculate the volume of carbon dioxide gas that is produced.be sure your answer has the correct number of significant digits.

Acalorimeter is to be calibrated: 51.203 g of water at 55.2 degree c is added to a calorimeter containing 49.783 g of water at 23.5c. after stirring and waiting for the system to equilibrate, the final temperature reached is 37.6 degree c. specific heat capacity of water (s = 4.18 j/g∙degree c). calculate the calorimeter constant. (smδt)warm water = -[(smδt)cold water + (calorimeterδtcold water)]

Air can be considered a mixture. which statement does not explain why?