The atomic mass of a metal is $27$ and its equivalent mass is $9$. What is the formula of its chloride?

Which of the following statements is not true about atomic mass?

An alloy of metals $X$ and $Y$ weighs $12 \ g$ and contains atoms $X$ and $Y$ in the ratio of $2:5$. The percentage of metal $X$ in the alloy is $20$ by mass. If the atomic mass of $X$ is $40$,what is the atomic mass of metal $Y$ (in $amu$)?

Sulfur forms two chlorides,$S_2Cl_2$ and $SCl_2$. The equivalent mass of sulfur in $SCl_2$ is $16$. What is the equivalent mass of sulfur in $S_2Cl_2$?

$1 \ amu$ is equal to

Sulphur forms the chlorides $S_2Cl_2$ and $SCl_2$. The equivalent mass of sulphur in $SCl_2$ is $....... \ g/eq$.