Question

question 13 (5 points)
air is a(n)
heterogeneous mixture.
element.
compound.
homogeneous mixture.
none of the above.
question 14 (5 points)
the phrase \ability to do work\ is a definition of
heating.
energy.
specific heat.
cooling.

Explanation:

• For Question 13: Air is composed of nitrogen, oxygen, carbon - dioxide and other gases uniformly distributed, so it is a homogeneous mixture. A heterogeneous mixture has visibly different components, an element is a pure substance made of only one type of atom, and a compound is a pure substance made of two or more different types of atoms chemically bonded.
• For Question 14: Energy is defined as the ability to do work. Heating and cooling are processes related to heat transfer, and specific heat is the amount of heat per unit mass required to raise the temperature by one degree Celsius.

Answer:

Question 13: D. homogeneous mixture
Question 14: B. energy