The following data was collected from $1$ trial of an experiment similar to the procedure

described in the lab handout.

Table $1.$ Solution volumes for Trial $1($all volumes are in $mL).$

After $49\mathrm{.}7$ seconds, the reaction mixture turns blue, indicating that all of the $S_2{O}_3^{2-}$ has

completely reacted. What is the change in molar concentration of $S_2{O}_3^{2*}([S_2{O}_3^{2-}])$ for Trial

$1($include appropriate $+/-$ sign$)?$

$(1pt)$

What is the change in molar concentration of $S_2{O}_8^{2*}$ for Trial $1?$ Use the balanced chemical

equations from the lab handout.

$(1$ pt$)$

Calculate the rate of reaction $(-\frac{S_2{O}_8^2}{}t)$ for Trial $1.$

Balanced chemical equations:

$1.$ S$2$O$8^(2-)($aq$)+2$ I$^(-)($aq$)->2$ SO$4^(2-)($aq$)+$ I$2($aq$)$

$2.$ I$2($aq$)+2$ S$2$O$3^(2-)($aq$)->2$ I$^(-)($aq$)+$ S$4$O$6^(2-)($aq$)$

rate $=-[$S$2$O$8^(2-)]/$t $=-(1)/(2)[$I$^(-)]/$t $=+(1)/(2)[$SO$4^(2-)]/$t $=+[$I$2]/$t