Question

A pair of eyeglass frames are made of an epoxy plastic (coefficient of linear expansion = 1.30 ✕ 10⁻⁴°C⁻¹). At room temperature (20.0°C), the frames have circular lens holes 2.21 cm in radius. To what temperature must the frames be heated if lenses 2.22 cm in radius are to be inserted into them?
A wire is 20.5 m long at 2.50°C and is 1.12 cm longer at 34.5°C. Find the wire's coefficient of linear expansion (in (°C)⁻¹).

A sample of pure copper has a mass of 14.8 g. Calculate the number of moles in the sample and copper atoms in the sample.

(a) moles in the sample

moles

(b) copper atoms in the sample

atoms

Answer 1