Alright this to me seems to be the answer C if it’s not then that’s cuz I’m guessing
Answer:
options B,C and E are correct conditions for forming hydrogen bonds.
Explanation:
In order for particles to stick together or shows certain characteristics, there must be a bond of attractions that is making them to be able to stay together. Some of these attractions are strong while some are weak. The kind of attraction that is being considered in this question is the hydrogen bonding which is considered as part of the weak forces of attractions.
In order for hydrogen bonds to occur, there must be hydrogen atoms [option B is correct] and a much more electronegative elements such as oxygen, Fluorine and Nitrogen. Hence, option C is correct.
Since the Fluorine or oxygen or nitrogen have much more electronegative properties than hydrogen, it causes a partial negative charge on Fluorine or oxygen or nitrogen and a partial positive charge on the Hydrogen. Thus, option E is correct.
Answer:
0.4912 kJ/K
Explanation:
Using steam table, the properties of water at stage 1 can be determined:
= 400 kPa
= 60°C
Therefore, from steam table:
specific volume 
entropy 
Calculating the specific volume of water after the partition is removed, since the mass is constant and volume of water is doubled:

Final pressure of water in the tank = 
dryness factor after removing the partition

Therefore:

Thus, the entropy change is:
Δs = 
Therefore, the entropy change of water is 0.4912 kJ/K
Answer : The number of drops it takes from a dropper to dispense 1.0 ml of ethanol is, 20 drops
Solution : Given,
Density of ethanol = 0.80 g/ml
Mass of ethanol = 0.60 g
First we have to calculate the volume of ethanol.
Formula used : 


The volume of ethanol is, 0.75 ml
Now we have to calculate the number of drops it takes from a dropper to dispense 1 ml of ethanol.
As, the number of drops in 0.75 ml of ethanol = 15
So, the number of drops in 1.0 ml of ethanol = 
Therefore, the number of drops it takes from a dropper to dispense 1.0 ml of ethanol is, 20 drops