Bonding In Metal Carbonyls

Step 1: Understanding the oxidation state of Ni in Ni(CO) .
In Ni(CO) , nickel has an oxidation number of 0 because carbon monoxide (CO) is a neutral ligand and does not affect the oxidation state of the metal.

Step 2: Explanation of the options.
- (1) Ni(CO) has zero oxidation number for Ni: This is correct because Ni in Ni(CO) has oxidation state 0.
- (2) Ni(CO) has oxidation number +4 for Ni: This is incorrect. Ni has oxidation state 0, not +4, in this complex.
- (3) Ni(CO) is metal: This is correct as Ni is the central metal in the complex.
- (4) CO is gas: This is correct. CO is a gas at room temperature.

Step 3: Conclusion.
The correct answer is (2) Ni(CO) has oxidation number +4 for Ni.

Step 1: Formula / Definition}

Step 2: Calculation / Simplification}
Amylose: -1,4 linkages (starch component)
Amylopectin: -1,4 and -1,6 linkages (branched starch)
Cellulose: -1,4 linkages
Both amylose and amylopectin have -linkages. Question asks "which" singular - amylose is the straight-chain -polymer.
Step 3: Final Answer