Standard enthalpy is zero for

Standard enthalpy is zero for elements not for compounds: Standard enthalpy of

$O_2\left(g\right),S\left(\alpha \right),C\left(graphite\right),B{r}_2\left(l\right),Na\left(s\right)$
 etc....zero Standard enthalpy of a  compound is equal to its standard  enthalpy of formation