Answer:
100ml of a stock 50% KNO3 solutions are needed to prepare 250ml of a 20% KNO3 solution.
Explanation:
In the given question it is mentioned that
S1=50%
V2=250ml
S2= 20%
We all know that
V1S1=V2S2
∴V1= V2×S2÷S1
∴V1= V2S2×1/S1
∴V1= 250×20÷50
∴V1= 100ml
Let MM(x) be the molar mass of x.
MM(Pb) : MM(PbO)
=207.21 : 223.20 = 451.4 g : x g
cross multiply and solve for x
x=223.2/207.21*451.4
= 486.23 g
Percentage yield = 365.0/486.23= 0.75067 = 75.07% (rounded to 4 sign. fig.)
Less friction to stop the wheel from turning
That depends. there are 2 possible answers.
H
C - C = C - H gives a different answer on the right than on the left.
One the left side, the second Carbon is attached to a double bond and has but one hydrogen attached to it.
The Carbon on the right of the double bond has 2
H
C- C = C - H
H
I'm not sure what you should put. It's one of those things that I would repeat my argument and submit it.
