Answer:
B: They are the results of many experiments over a long period of time.
Explanation:
X

H has a positive 1 charge. This means that having 3H = +3<span>. This is a neutral compound so x= -3 because X+3H= 0
Y</span>

is also neutral so 2X+Y= 0
we know X=-3 So, 2(-3)+Y=0
-6+y=0
Y=+6 charge
Answer: The valency of X is -3.
The valency of Y is 6
Balanced there are 2 Al, 6 oxygens on both sides.
Answer:
In 1935
First synthetic fiber produced by man
Got it's name from Cities of New York And London