Answer:
1.67 M
Explanation:
The following data were obtained from the question:
Initial volume (V1) of solution = 250 mL
Initial Molarity (M1) of solution = 0.5 M
Final volume (V2) of solution = 75 mL
Final Molarity (M2) of solution =?
Thus, we can obtain the final molarity of the solution by using the following formula:
M1V1 = M2V2
0.5 × 250 = M2 × 75
125 = M2 × 75
Divide both side by 75
M2 = 125 /75
M2 = 1.67 M
Thus, the new Molarity of the solution is 1.67 M.
Answer:
First, the microwaves transmit kinetic energy to the water molecules of the food, heating the water molecules. Only, those that are not very deep into the food.
Second, the hot water molecules transmit heat by conduction to the other parts of the food.
Explanation:
1) Microwaves are a form of electromagnetic radiation. The same as any wave, they carry energy.
2) The wave length of microwaves are in the range of 0.001 mm to 1 m (shorter than radio waves and longer than infrared)
3) The microwaves of an oven, used to heat food, have a wave length aroun 12 cm.
4) The microwaves transmit energy to the water molecules in the food, by increasing the kinetic energy of water molecules. As result, the water molecules get hotter. Microwaves only penetrate about 1 cm inside the food (a potato for example) and from that the heat is transferred by conduction to the inner parts of the food.
Answer:
Q = 1964 J
Explanation:
Data Given:
latent heat of fusion for Lead (Lf)= 23.1 J/g
amount of ice (mass) = 85.0 gram
heat required to melt lead (Q) =?
Solution:
Latent heat of fusion: the amount of heat that required to melt certain amount of a substance. The total heat absorbed by substance is proportional to the total heat of fusion of the material.
Formula Used
Q = mLf
Q = heat required to melt a substance
m = mass of the substance
Lf =latent heat of fusion
put values in above formula
Q = mLf
Q = 85 g x 23.1 J/g
Q = 1964 J
To answer this question, you need to know <span>Graham's Law of Effusion/Diffusion formula. In this formula, the rate of diffusion/effusion would be influenced by the mass. As the molecule has bigger mass, the rate should be slower because it will be harder to pass the membrane. The calculation should be:</span>
<span>Rate 1 / Rate 2 = √[M2/M1]
</span>4.11/1= √[M2/2]
M2=33.78 g/mol