What is heterogenous mixture​

What are the similarities between compounds and mixtures?

Why is any chemical reaction always balanced? give reasons and explain the easiest way to solve the balancing problems in chemical equations with stoichiometric coefficients upto 20 as hit and trial doesn't always work. give full reasoning

0.88 moles of n2o5 (g) was placed in a sealed 1.00 l vessel. calculate the equilibrium concentration of n2o5. no2, and o2 and the equilibrium constant after equilibrium has been reached by 65.0% of the n2o5 decomposing.