We will get the molality from this formula:
Molality = no.of moles of solute / Kg of solvent
So first we need the no.of moles of KNO3 = the mass of KNO3 / molar mass of KNO3
no.of moles of KNO3 = 175 / 101.01 = 1.73 mol
By substitution in the molality formula:
∴ molality = 1.73 / (750/1000) = 2.3 Molal
Answer:
21 years
% of parent isotope remaining before safe
6.25%
Explanation:
Answer:
Energy added to solid water will turn it into liquid water; add energy into liquid water and it will be turned into water vapor.
Explanation:
Adding energy is basically adding heat; the more heat, the more excited the molecules of H2O gets. In solid water, the molecules aren't really moving because they don't have a lot of energy, so it is solid. In liquid water (which is water in room temperature), it has a medium amount of energy; the molecules aren't stuck together but it isn't completely dispersed, so it is in liquid form. However, in water vapor, the energy becomes very high and the molecules are excited. The hydrogen bonds holding the molecules together break and the water is released as a vapor.
Ans: Final volume = 25.0 ml
<u>Given:</u>
Initial volume V1 = 50.0 ml
Initial pressure P1 = 20.0 atm
Final pressure P2 = 40.0 atm
<u>To determine:</u>
The final volume V2
<u>Explanation:</u>
Ideal gas equation: PV = nRT
under constant temperature, T and number of moles n we have:
PV = constant
or, P1V1 = P2V2
V2 = P1V1/P2 = 20*50/40 = 25 ml.
