Question

C-CO2-H2CO3-K2CO3-KHCO3

Answer 1

1)  $C + O _{2} = CO _{2}$
2)  $CO _{2} + H _{2} O = H _{2} CO _{3}$
3)  $H _{2} CO _{3} + 2KOH = K _{2} CO _{3} + 2H _{2} O$
4)  $H _{2} CO _{3} + K _{2} CO _{3} = 2KHCO _{3}$
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