Place the mixture in hot water and stir well.
<span>The KNO3 is very soluble in hot water. </span>
<span>Use a fine filter paper and filter off the sand. </span>
<span>The sand will be separated from the KNO3 solution. </span>
<span>The water can now be evaporated from the solution by further, gentle heating leaving the solid in the container.</span>
<span>1. Coherence Theory (Theory of Coherence)
Based on this theory, a knowledge considered to be true if the knowledge kehoren with the knowledge that exists and has been proven to be true. In the study of mathematics this is usually called the deductive nature.
2. Correspondence Theory (Theory of corespondence)
Based on this theory, a knowledge considered to be true if the knowledge of having a relationship with a reality that is true. This theory is based on the empirical fact that knowledge is true if there are facts that support that is true knowledge. Thus the truth here is based on inductive inference.
3. Pragmatic Theory (Theory of Pragmatism)
According to this theory, knowledge is said to be true if the knowledge is seen practically completely or have properties that true practicality. Followers of this theory argue that knowledge is true if it has keguanaan practical<span>.</span></span>
Answer: The mass density is 1166.36 
.
Explanation:
Given: Weight of sample in air 
= 500 N
Weight of sample in alcohol 
= 200 N
Specific gravity = 0.7 = 
Formula used to calculate Buoyant force is as follows.
Hence, volume of the material is calculated as follows.
where,
= Buoyant force
= specific gravity
g = acceleration due to gravity = 9.81
Substitute the values into above formula.
Now, mass of the material is calculated as follows.
Therefore, density of the material or mass density is as follows.
Thus, we can conclude that the mass density is 1166.36 .
