How much quantity of chemicals i do have to mix to create carbon dioxide to become paste?
quantity of sodium bicarbonate?
quantity of acid?(what kind of acid)
quantity of water?
how much heat?
Well, there's no not one solution for this task. You can use different kinds of acids with different level of dilution by water (different concentration). But there is one requirement for all these acids - they must be stronger than H2CO3. Only in this case CO2 can be produced. Examples of acids are HCl, HBr, HI, H2SO3, H2SO4, HNO3 and others. Quantity of water which you need depends upon concentration of acid.