Answer:
5. gains two electrons.
Explanation:
In order to determine the most stable monoatomic ion of oxygen, we need to consider the octet rule: atoms will gain, lose or share electrons to complete their valence shell with 8 electrons.
Oxygen is in the Group 16 in the Periodic Table, so it has 6 valence electrons. Therefore, it will gain two electrons to have the electron configuration of the closest noble gas.
Answer : The density of a sample of chlorine gas is, 12.59 g/L
Explanation :
To calculate the density of chlorine gas we are using ideal gas equation.

where,
P = pressure of chlorine gas = 4.5 atm
V = volume of chlorine gas = 12.6 L
n = number of moles of chlorine gas
w = mass of chlorine gas
R = gas constant = 0.0821 L.atm/mol.K
T = temperature of chlorine gas = 
M = molar mass of chlorine gas = 71 g/mol
Now put all the given values in the above formula, we get:



Therefore, the density of a sample of chlorine gas is, 12.59 g/L
Answer:
A.) Atoms contain electrons
Explanation:
J.J. Thomson conducted an experiment in which he took a gas at low pressure in a discharge tube and applied high voltage current. When he did so, he noticed that there are some particles emitting from cathode going towards the anode. <u>Then he concluded that they are negatively charged particles and coined them electrons.</u>
<u>Hence, out of the options:- A.) Atoms contain electrons is correct.</u>
Answer:
4. mutualism - both benefit
5. Commensalism- one benefits while the other is not affected
"Mutualism is a symbiotic relationship in which both species benefit. Commensalism is a symbiotic relationship in which one species benefited while the other species is not affected."