Answer:
Humidity is the measure of how much water vapor is in the air.
The molality is 0.54 M when 1.34 moles of NaCl is present in 2.47 kg of solvent.
<u>Explanation:</u>
Molality is the measure of how much of amount of solute is dissolved in the solvent. So it is calculated as the ratio of moles of solute to the grams of solvent.
As in this case, the solute is NaCl and solvent is unknown. So the moles of solute is given as 1.34 moles and the mass of solvent is given as 2.47 kg.
Hence,
Thus, the molality is 0.54 M when 1.34 moles of NaCl is present in 2.47 kg of solvent.
Answer:
Breaker A
Explanation:
Because the temperature is cooler in A then the rest
If a piece of charcoal is taken and set on fire it will evolve CO2 and heat. Charcoal is solid but carbon dioxide is gaseous. This is an example of change of state and evolve of heat during chemical reaction.
Answer:
Explanation:
The work function of the sodium= 495.0 kJ/mol
It means that
1 mole of electrons can be removed by applying of 495.0 kJ of energy.
Also,
1 mole =
So,
electrons can be removed by applying of 495.0 kJ of energy.
1 electron can be removed by applying of of energy.
Energy required =
Also,
1 kJ = 1000 J
So,
Energy required =
Also,
Where,
h is Plank's constant having value
c is the speed of light having value
So,
Also,
1 m = 10⁻⁹ nm
So,