Answer:
D. The oxygen side is partially negative because electrons are pulled toward the oxygen side.
Explanation:
The water molecule is polar by the virtue of covalent bonds and the hydrogen bonds within and between its molecule.
The oxygen side is partially negative because the electrons are pulled toward the oxygen side.
Between oxygen and hydrogen that makes up the water molecule, oxygen is more electronegative.
An electronegative atom has more affinity for electrons. Since the electrons in the molecule of water is shared between hydrogen and oxygen, the more electronegative specie which is water draws the electron more to itself.
This leaves a net negative charge on the oxygen atom.
Answer:
The amount of energy required is 
Explanation:
The energy required to convert the ice to steam is the sum of:
1) Energy required to raise the temperature of the ice from -20 to 0 degree Celsius.
2) Latent heat required to convert the ice into water.
3) Energy required to raise the temperature of water from 0 degrees to 100 degrees
4) Latent heat required to convert the water at 100 degrees to steam.
The amount of energy required in each process is as under
1) 
where
' is specific heat of ice =
2) Amount of heat required in phase 2 equals

3) The amount of heat required to raise the temperature of water from 0 to 100 degrees centigrade equals

where
' is specific heat of water=
4) Amount of heat required in phase 4 equals

Thus the total heat required equals 
In a direct current (DC) electrical circuit, the voltage (V in volts) is an expression of the available energy per unit charge which drives the electric current (I in amperes) around a closed circuit. Increasing the resistance (R in ohms) will proportionately decrease the current which may be driven through the circuit by the voltage.
Each quantity and each operational relationship in a battery-operated DC circuit has a direct analog in the water circuit. The nature of the analogies can help develop an understanding of the quantities in basic electric ciruits. In the water circuit, the pressure P drives the water around the closed loop of pipe at a certain volume flow rate F. If the resistance to flow R is increased, then the volume flow rate decreases proportionately. You may click any component or any relationship to explore the the details of the analogy with a DC electric circuit.