Answer:
They had a negative charge
Explanation:
Answer: Option (a) is the correct answer.
Explanation:
It is known that elements which have completely filled octet when they are present in neutral state then they do not need to gain or lose an electron. Hence, the element becomes unreactive in nature.
For example, neon is a noble gas whose atomic number is 10 and its electronic distribution is 2, 8. As they have completely filled orbitals so they do not react with other elements.
As a result, they are rarely found in combination with other elements.
Thus, we can conclude that the Group 8A(18) elements are unreactive and are rarely found in combination with other elements.
Answer:
36°C
Explanation:
Given parameters:
Mass of aluminum = 725g
Quantity of heat = 2.35 x 10⁴J
Unknown:
Temperature change = ?
Solution:
To solve this problem, we simply use the expression below:
The quantity of energy is given as:
Q = m C Δt
Q is the quantity of energy
m is the mass
C is the specific heat capacity of aluminum = 0.9J/g°C
Δt is the change in temperature
The unknown is Δt;
Δt = 
= 
= 36°C
Answer : The mole fraction and partial pressure of 
and 
gases are, 0.267, 0.179, 0.554 and 1.54, 1.03 and 3.20 atm respectively.
Explanation : Given,
Moles of 
= 1.79 mole
Moles of 
= 1.20 mole
Moles of = 3.71 mole
Now we have to calculate the mole fraction of and gases.
and,
and,
Thus, the mole fraction of and gases are, 0.267, 0.179 and 0.554 respectively.
Now we have to calculate the partial pressure of and gases.
According to the Raoult's law,
where,
= partial pressure of gas
= total pressure of gas = 5.78 atm
= mole fraction of gas
and,
and,
Thus, the partial pressure of and gases are, 1.54, 1.03 and 3.20 atm respectively.
