Answer : Urea was the first organic compound synthesized in laboratory.
Explanation : The German chemist named Friedrich Wöhler tried to obtain urea artificially by treating silver cyanate with ammonium chloride. He was successful in synthesizing this organic compound in the laboratory.
Answer: It completely dissociates in water is a characteristic of strong acid.
Explanation:
An acid which dissociates completely to give hydrogen ions 
is called a strong acid.
For example, HCl is a strong acid and it dissociates completely as follows.
Strong acids are able to conduct electricity in water as more number of ions are present in the solution as compared to the ions present in a solution of weak acid.
Strong acids increase the concentration of 
ions.
Thus, we can conclude that it completely dissociates in water is a characteristic of strong acid.
Answer:
True
Explanation:
The given statement is true.
A scientific model is defined as the mathematical and physical representation of a process or event. Scientists perform several observations or experiment and find a connection between them to prove a scientific finding.
A scientific model has the ability of explanatory power which helps to make things easier to understand using diagrams and consistency across contexts. Testing and prediction power in scientific models leads to strong predictions and able to convince people using an appropriate model.
Hence, the correct answer is "true".
