The atomic theory started with Democritus, who stated that all space was made up of indivisible particles called atoms, though Aristotles refuted that statement by saying that matter didn’t exist, he believed in the four elements: air, fire, water, and earth. Then came Dalton, who revived Democritus’s ideas and proposed the law of multiple proportions, he revived the idea that all space was made of atoms. Soon after, J.J Thompson discovered the electron by using cathode rays. Max Planck developed the quantum theory by stating that electromagnetic radiation could only be emitted in quantized form (later called quanta). Einstein furthered this idea with studies of light. Robert Millikan eventually measured the charge of a single electron. Ernest Rutherford used a gold foil experiment and discovered the nuclei, considering his alpha particles were deflected by some object. Niels Bohr made the atomic model with electrons spinning around an atom’s nucleus, Erwin Schrodinger describes how electrons have wave like properties. James Chadwick then discovers the neutron!
There ya have it!
Answer:
Partial pressure of 
in the gas was 733 torr and mass of 
in the sample was 2.12 g.
Explanation:
a) Total pressure of gas = (partial pressure of water vapour)+(partial pressure of )
Here partial pressure of water vapour is 21 torr and total pressure of gas is 754 torr.
So, partial pressure of = (total pressure of gas)-(partial pressure of water vapour) = (754 torr) - (21 torr) = 733 torr
b) Lets assume that behaves ideally. Hence-
PV=nRT
where P is pressure of , V is volume of , n is number of moles of , R is gas constant and T is temperature in kelvin
here P = 733 torr = 
= 0.9646 atm
V = 0.65 L, R = 0.082 L.atm/(mol.K), T=(273+22)K = 295 K
So, 
= 
= 0.0259 moles
As 3 moles of are produced from 2 moles of therefore 0.0259 moles of are produced from 
moles or 0.0173 moles of .
Molar mass of = 122.55 g
So mass of in sample = 
= 2.12 g
Not sure, just setting up account
Well if we think about a food pyramid there are consumers that eat plants and if there are no plants to eat then those primary consumers die. Which means that the secondary consumers have no prey to eat and die as well, eventually leading to the top predators who have absolutely nothing to feed on.
They are the most affected because energy level decreases the higher up you go so the top predators need to eat more and if there is less and less to eat they die out quicker
3-B
4-C
5-A
6-A
7-C
8-B
9-A
10-B
