Plz me with this question, i am stuck

In numbering carbon atoms in the parent chain of a hydrocarbon, why would you number from right to left, rather than left to right

Which statement about hf is true? it is zero for any compound in its standard state. it is positive when the bonds of the product store more energy than those of the reactants. it is negative when a compound forms from elements in their standard states. it is zero for any element that is in the liquid state.

How many moles are contained in 5.6 l of h2 at stp