JAMB - Chemistry (2012 - No. 40)
Carbohydrates are large molecules with the molecular formula C\(_x\)(H\(_2\)O)\(_y\). In which of the following pairs is x not equal to y?
glucose and starch
maltose and starch
sucrose and fructose
galactose and starch
Giải thích
Glucose = C\(_6\)(H\(_2\)O)\(_6\)
= C\(_6\)H\(_{12}\)O\(_6\)
Maltose = C\(_{12}\) (H\(_2\)O)\(_{11}\)
= C\(_{12}\)H\(_{22}\)O\(_{11}\)
Starch = C\(_6\) (H\(_2\)O)\(_5\)
= C\(_6\)H\(_{10}\)O\(_5\)
Sucrose = C\(_{12}\) (H\(_2\)O)\(_{11}\)
= C\(_{12}\)H\(_{22}\)O\(_{11}\)
Fructose = C\(_6\)(H\(_2\)O)\(_6\)
= C\(_6\)H\(_{12}\)O\(_6\)