a, goi hỗn hợp ankan là $C_nH_{2n+2} , m = 0,48 + 1,16 = 1,64$ gam$n_{CO_2} = n_{CaCO_3} = 11/100 = 0,11$ mol
=> $m_C = 0,11.12 = 1,32 g => m_H = 1,64 - 1,32 = 0,32$ gam
=> $n_C/n_H = n/2n+2 = 0,11/0,32 => n = 2,2$
=> $n_{ankan} = 0,11/2,2 = 0,05$ mol
$n_{H_2O} = 1/2n_H = 0,16$ mol => $m_{H_2O} = 2,88$ gam