Answer:
protons have a positive, neutrons have no charge and electrons have a negative chage
Explanation:
Mass number = number of protons + number of neutrons
number of protons = atomic number =7
number of neutrons= mass number - number of protons=16-7=9
Answer is B.9.
Extensive property is that which depends on the amount of matter in a sample. For example: mass, volume, size are all extensive properties
Intensive properties are independent of the amount of matter. These include; boiling point, melting point, color and so on.
In the given examples:
Both sample A and B have the same volume (1000 ml) i.e. the same extensive property. However, they have different freezing points i.e. different intensive property.
Ans: D) The two substances are not the same because their intensive property is different.
Answer:
d. Adding 5% HCl solution to the crude reaction mixture will protonate aniline increasing its solubility in the aqueous solution.
Explanation:
On this case, we have to check the <u>structures of each compound</u> (figure 1). For naphthalene we dont have <u>any functional groups</u> therefore, the addition of HCl or NaOH it will not affect naphthalene so <u>we can discard "B" and"C".</u>
When we add HCl solution we will have the production 
the presence of this <u>hydronium ion will protonate the acid</u>, so we can <u>discard a.</u>
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Finally, for d when we add the <u>hydronium ion will react with aniline</u> (a base) and will produce an <u>ammonium ion</u>. This ammonium ion have a <u>positive charge</u>, therefore the <u>polarity will increase</u> and the molecule would be more soluble on water (figure 2).
I hope it helps!
