<span>Errors can come from various sources: the obtainer of the data, the measuring instrument, the setting and etc. Errors are what makes your measurement invalid and unreliable. There are two types of error which is called the systematic error and the random error. Each error has different sources. Words that were mentioned –invalid and unreliable are very important key aspects to determine that your measure is truly accurate and consistent. Some would recommend using the mean method, doing three trials in measuring and getting their mean, in response to this problem.</span>
Answer:
E - Atomic mass is calculated by weighted atomic average using all the isotope data available.
G - Mass number is equal to the sum of protons and electrons in an atom.
Explanation:
Take an element

- Mass no is 25 and atomic no is 12.
Try to understand all the rules and laws like:
Aufbau Principle
Hund's rule
Pauli exclusion principle...
Then, you should understand the way in which you can fill the electrons in the orbitals!!
Answer: Secondary amines react with the nitrosonium ion to generate <span>
<u>N-Nitrosoamines</u>.
Explanation: Nitosonium Ion is generally utilized in the formation of
Diazonium Salts which are considered excellent starting Material from synthesis point of View. Diazonium salts are formed by reacting
Primary Amine or
Anilines with Nitrosonium Ions. In our case, the Amine given is Secondary. So, reaction of <em>Sec.</em> Amines with Nitrosonium Ions stops after the formation of N-Nitrosoamine as there is no Hydrogen attached to Nitrogen atom of Amine to be eliminated and form a double and eventually triple bond with the Nitrogen atom of Nitrosonium Ion.</span>