Đáp án:
Giải thích các bước giải:
$3/$
$a,4Na+O_2\buildrel{{t^o}}\over\longrightarrow$ $2Na_2O$
$b,2Zn+O_2\buildrel{{t^o}}\over\longrightarrow$ $2ZnO$
$c,S+O_2\buildrel{{t^o}}\over\longrightarrow$ $SO_2$
$d,4P+5O_2\buildrel{{t^o}}\over\longrightarrow$ $2P_2O_5$
$g,2SO_2\buildrel{{t^o,xt}}\over\longrightarrow$ $2SO_3$
$h,C_2H_4+O_2\buildrel{{t^o}}\over\longrightarrow$ $2CO_2+2H_2O$
$4/$
$PTPƯ:2KMnO_4\buildrel{{t^o}}\over\longrightarrow$ $K_2MnO_4+MnO_2+O_2↑$
$n_{O_2}=\frac{6,72}{22,4}=0,3mol.$
$Theo$ $pt:$ $n_{KMnO_4}=2n_{O_2}=0,6mol.$
$⇒m=m_{KMnO_4}=0,6.158=94,8g.$
$Theo$ $pt:$ $n_{MnO_2}=n_{O_2}=0,3mol.$
$⇒x=m_{MnO_2}=0,3.87=26,1g.$
chúc bạn học tốt!
