Answer:
That information is better presented and analyzed in a table.
This table shows you all the information and the answers:
Substance melting point boiling point room temperature conclusion
°C °C °C (state)
A 0 100 25 liquid
B 50 200 25 solid
C -150 10 25 gas
Explanation:
1) Substance A at 25° is above the melting point and below the boiling point, then it is liquid (just like water)
2) Substance B at 25°C is below the melting point, so it is solid.
3) Substance C at 25°C is above the boiling point, so it is gas.
Answer:
The general equation for an exothermic reaction is: Reactants → Products + Energy.
Answer : The Lewis-dot structure of 
is shown below.
Explanation :
Lewis-dot structure : It shows the bonding between the atoms of a molecule and it also shows the unpaired electrons present in the molecule.
In the Lewis-dot structure the valance electrons are shown by 'dot'.
The given molecule is,
As we know that hydrogen has '1' valence electron and nitrogen has '5' valence electrons.
Therefore, the total number of valence electrons in = 5 + 3(1) = 8
According to Lewis-dot structure, there are 6 number of bonding electrons and 2 number of non-bonding electrons.
Now we have to determine the formal charge for each atom.
Formula for formal charge :
Hence, the Lewis-dot structure of is shown below.
Mercury expands when it is heated. This process is called thermal expansion.
Because the rate at which water vapour condenses gets increase slowly to get equal to the rate of evaporation of the water.
Explanation:
When a bottle is partly filled with liquid water is leaves space for vapours to escape and get condensed equally.
When sealed and kept below the lamp the rate of condensation increases due to the empty space in the bottle for getting vapours cool down.
A point arrives when evaporation equates the condensation of the liquid in bottle becomes stable because vapours cannot pass the bottle eventually condense and become liquid.
