The solid form of a substance is usually more dense than its
liquid and gaseous forms. Similarly the liquid form is usually more dense than
the gaseous form. Ice floating in water is an exception that breaks the general
density rule. So option “A” is the correct option in regards to the given
question. In case of ice formation, actually the density of water decreases by
about 9%. This is the main reason behind ice floating in water. Pure water has
the maximum density at 4 degree centigrade.
Hept for 7, hence the number is seven.
The answer is 4.9 moles.
Solution:
Using the equation for boiling point elevation Δt,
Δt = i Kb m
we can rearrange the expression to solve for the molality m of the solution:
m = Δt / i Kb
Since we know that pure water boils at 100 °C, and the Ebullioscopic constant Kb for water is 0.512 °C·kg/mol,
m = (105°C - 100°C) / (2 * 0.512 °C·kg/mol)
= 4.883 mol/kg
From the molality m of the solution of salt added in a kilogram of water, we can now find the number of moles of salt:
m = number of moles / 1.0kg
number of moles = m*1.0kg
= (4.883 mol/kg) * (1.0kg)
= 4.9 moles
Answer:
The average pressure in the container due to these 75 gas molecules is 
Explanation:
Here Pressure in a container is given as

Here
- P is the pressure which is to be calculated
- ρ is the density of the gas which is to be calculated as below

Here
mass is to be calculated for 75 gas phase molecules as

Volume of container is 0.5 lts
So density is given as

is the mean squared velocity which is given as

Here RMS is the Root Mean Square speed given as 605 m/s so

Substituting the values in the equation and solving

So the average pressure in the container due to these 75 gas molecules is 
The answer to the question :
The atoms of Group B elements _____ electrons when they form ions .
is :
D) lose
The atoms of Group B elements lose electrons when they form ions because these elements are metals.