Which of these is a chemical property?

a. mercury is a dense liquid.
b. iodine vapor has a purple color.
c. aluminum is a very conductive metal.
d. ice melts at 0°c.
e. iron rusts in wet weather.

A chemical property is a property of a material that is obvious or evident after a chemical reaction. Looking at all the choices, A to D are all physical properties. They only describe the physical state or property of a material. Only E is a chemical property because it talks about rusting which is a form of a chemical reaction.

Adozen is 1221/12 = 1.751.75 x 12 = 21therefore, 1.75 is the answer.

Determine the  wavelength of light emitted when an electron  in an li2+ ion  makes a transition from an orbital with n  =  6 to an orbital with n  = 5.