Answer:
<em><u>A balance and a beaker of water!</u></em>
Explanation:
Krishne wants to measure the mass and volume of a key. The tools that are to be used are – a balance and a beaker of water.
Mass will be represent with the amount of matter that is in an object. This will be measured in terms of kilogram. The mass can easily be measured with balance.
Volume is the quantity of matter that is in the object. This is measured in terms of cubic meter. If you drop the key in a beaker of water, the water inside the beaker will increase and this increases the volume of water that will be equal to volume of key.
Answer:
1) 
2) 
3) 
4) The Molecules do not burn because of the presences of hydrogen bond in place
Explanation:
From the question we are told that
latent heat of vaporization for water at room temperature is 2430 J/g.
1)Generally in determining the molar mass of water evaporated we have that
-One mole (6.02 x 10. 23 molecules)
-Molar mass of water is 18.02 g/mol
Mathematically the mass of water is give as


Therefore


b)Generally the evaporation speed V is given as
Mathematically derived from the equation
To Give



c)Generally the equation for velocity 
Therefore
Effective temperature T is given by

where


4) The Molecules do not burn because of the presences of hydrogen bond in place