Ethane, C2H6, burns in oxygen as follows. C2H6 + O2  CO2 + H2O
What mass of carbon dioxide is produced if 10.2 g of ethane and 44.6 g of oxygen are mixed and ignited? ( Ans = 29.9 g of carbon dioxide check 29 or 20)

fe 55.85 g/mol and h2o 18.02 g/mol.

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.

nacl or sodium chloride is an ionic compound. this is because an ionic compound pertains to a compound that consists of positively and negatively charged ions. in this case, na (sodium) has a tendency to lose one electron when it reacts with with other atoms, so the resulting sodium ion contains 11 protons and 10 electrons, thus making it positively charged (na+), when chlorine reacts, it usually gains one electron to form an ion called chloride, thus making it negatively charged ( since the ions are oppositely charged, they attract.