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How much time (in a minute) is usually required for the passing of Co2 through the mould?

How much time (in a minute) is usually required for the passing of Co2 through the mould? Correct Answer One

In Co2 moulding, mould of sand is hardened by passing of Co2 for about one minute. The Co2 gas forms a weak acid that hydrolyzes the sodium silicate (Na2O, SiO2) solution to form amorphous silica gel which acts as the bond and sodium silicate itself also provides some bonding action.

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