Question

Homogenous materials have:
(A) uniform composition
(B) uniform properties
(C) both A and B
(D) different composition but same properties

Answer 1

Hint: Think about what the term ‘homogenous’ means. Think about which category solutions come in. We know solutions and colloids have different properties. Think about which of their properties are different and the reason behind it. Try to define a solution to get the answer.

Complete step by step solution:
-Homogenous materials are the substances which are uniform throughout.
-An example of homogeneous material is a true solution like salt water. Salt is completely dissolved in water. When salt gets completely dissolved in water, there is no solid salt left in the solution. All salt molecules dissociate and get solvated or hydrated. So, the solution will be uniform throughout and in the liquid phase only.
-Another example will be a pure metal block like gold. It will have the same gold particles oriented in the same fashion throughout and will show the same chemical as well as physical property.
-Heterogeneous materials are substances which do not have uniformity and are made of multiple phases and differ in chemical and physical properties. They have the varying composition of substances.
-An example is colloids. Colloids are mixtures in which two insoluble entities come together and form a mixture in which one of the entities is completely dispersed in the medium. For example, emulsions like milk. The emulsion is a colloid having two insoluble liquids mixed together. Milk is an emulsion of oil and water.
-Therefore, homogenous materials have uniform composition and properties.

Therefore, the answer is option (C).


Note: Remember, in homogenous materials, there is uniform composition like quartz which is the crystalline form of glass having long range order and orientation whereas, in heterogeneous materials, the composition is not fixed throughout the sample. It varies and might even have different phases mixed together, for example, gels in which air is mixed in liquid or aerosol in which gas is suspended in solid, etc.