Answer:
<em>Molar mass of the gas is 0.0961 g/mol</em>
<em></em>
Explanation:
The effusion rate of an unknown gas = 11.1 min
rate of effusion = 2.42 min
molar mass of hydrogen = 1 x 2 = 2 g/m
molar mas of unknown gas = ?
From Graham's law of diffusion and effusion, the rate of effusion and diffusion is inversely proportional to the square root of its molar mass.
from
=
where
= rate of effusion of hydrogen gas
= rate of effusion of unknown gas
= molar mass of H2 gas
= molar mass of unknown gas
substituting values, we have
=
4.587 =
= /4.587
= 0.31
= = <em>0.0961 g/mol</em>
Coal does not produce flame when burnt because it does not vapourizes
A. carbon
b. the carbon atoms in diamond have a lot of strong covalent bonds with other carbon atoms. which are conjoined in a 3d structure. This means the ‘giant covalent structure’ of diamonds is very difficult to break, making diamonds very hard.
However, the carbon atoms in graphite have less covalent bonds, and graphite is structured in sheets of atoms with weak forces holding them together - this means these sheets can slide off easily and come apart from the structure. Therefore, graphite is very soft.
Answer:
C. 0.50 mol
Explanation:
Number of mole= mass /molar mass
Mass of KF is given as 29g
The molar mass of KF= 39+19= 58g/mol
No of mole= mass/ molar mass
= 29g/58g/mol
1/2 mol= 0.5 mol