Answer:
option C is correct (250 g)
Explanation:
Given data:
Half life of carbon-14 = 5700 years
Total amount of sample = 1000 g
Sample left after 11,400 years = ?
Solution:
First of all we will calculate the number of half lives passes during 11,400 years.
Number of half lives = time elapsed/ half life
Number of half lives = 11,400 years/5700 years
Number of half lives = 2
Now we will calculate the amount left.
At time zero = 1000 g
At first half life = 1000 g/2 = 500 g
At second half life = 500 g/2 = 250 g
Thus, option C is correct.
Answer:
Plastic polymers
Explanation:
Plastic polymers are usually made up of synthetic and semi-synthetic polymers such as polyethylene, polystyrene etc.
Plastic polymers have a unique property called malleability. Malleability is the ability of a substance to be moulded into different sizes and shapes.
When hear is applied plastics gets soft and can be molded into different forms and then it becomes hardened after exposure to air(dried).
The plastic polymers are usually very cheap to produce in large quantities which is why it is very common in industries.
The correct answer is C, too deep in the Earth to collect. Hope this helps!
Molar mass (CaCl2) = 40.1 +2*35.5 = 111.1 g/mol
Molar mass (AlCl3) = 27.0 +3*35.5= 133.5 g/ mol
3CaCl2+Al2O3 -------->3CaO +2AlCl3
mole from reaction 3 mol 2 mol
mass from reaction 3mol* 111.1g/mol 2 mol*133.5g/mol
333.3 g 267.0 g
mass from problem 45.7 g x g
Proportion:
333.3 g CaCl2 ------- 267.0 g AlCl3
45.7 g CaCl2 -------- x g AlCl3
x=45.7*267.0/333.3= 36.6 g AlCl3
The mass of one mole of water it is 18 amu, but you need to find the mass of a molecule of water, therefore you calculate the mass of one mole of water, which is 18 amu and you divided by Avogadro's number which is 6,022 x 10^23. The result is 2,989 x 10^-23. Hope I helped you. If you have any questions ask :) Good luck.
