Answer:
Position D
Explanation:
One fourth of the Moon will be visible from Earth when the Moon is in position D. The reason why this is the right position is that the Moon will be in a position where the majority of its surface that is lighted by the Sun is facing the Sun. On the other hand, the angle is just right that about one quarter of the lighted part of the Moon is also facing the Earth. This will result in a perception from the Earth's view point that the Moon is lighted at one quarter of its surface.
Answer:
The total amount of heat released is 68.7 kJ
Explanation:
Given that:
mass of water = 94.0 g
moles of water = 94 / 18.02 = 5.216
80⁰C ------> 0⁰C --------> -30⁰C
Q1 = m Cp dT
= 94 x 4.184 x (0 - 80)
= -31463.68 J
= -31.43 kJ
Q2 = 6.01 x 10^3 x 5.216
= - 31348.16 J
= -31.35 kJ
Q3 = - 94 x 2.09 x 30
= - 5893.8 J
= -5.894 kJ
Total heat = Q1 + Q2 + Q3 = -31.43 kJ + (-31.35 kJ ) + (-5.894 kJ
) = -68.7 kJ
Total heat released = -68.7 kJ
Note that the "negative sign" simply indicates heat released, therefore no need to put it in the answer.
Answer: -
71
Explanation: -
From the diagram, we see that volume goes from 70 to 75 in 5 markings.
Each marking is for 1.
It is the most accuracy possible as there is no smaller marking.
Significant figures expresses the required amount of accuracy.
Thus the volume indicated from the diagram is 71 .
