Answer:
Step-by-step explanation:
a. 0.31
The number of mole of pure 11C (carbon-11) initially present is 0.2727 mole
<h3>Description of mole </h3>
The mole of a substance is related to it's mass and molar mass according to the following equation
Mole = mass / molar mass
With the above formula, we can obtain the number of mole of pure 11C. Detail below:
<h3>How to determine the mole of 11C</h3>
From the question given, the following data were obtained:
- Molar mass of 11C = 11 g/mol
- Mass of 11C = 3 g
- Mole of 11C =?
Mole = mass / molar mass
Mole = 3 / 11
Mole = 0.2727 mole
Therefore, the number of mole of pure 11C initially present is 0.2727 mole
Learn more about mole:
brainly.com/question/13314627
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Step-by-step explanation:
1) -5n+10n
= 5n
2) -x-9+2x-10
= 2x-x-9-10
= x-19
3) -5(x-10)-x
= -5x+50-x
= -6x+50
4) 9-5(1-7x)
= 9-5+35x
= 35x+4
5) y^2-x
= 3^2-2
= 9-2
= 7
Do the remain questions by yourself, you can do it!
