Day and night is due to the earth rotating. Seasons are due to the earth rotating on a slightly tilted axis, causing light to be shone on different parts of the earth more directly during different parts of the year. Constellations changing throughout the night are because of the earth moving and rotating. Throughout the year, the earth moves, causing us to be facing different directions in different parts of the year. The North Star does't move because it is close to Earth's line of axis, and therefore does not appear to move.
Sulfur will float, and iron will sink because each will retain its properties.
“Iron will float, and sulfur will sink because each will lose its properties” is <em>incorrect</em>. A substance will lose its properties only if it reacts to form a new substance.
“Both will float because they are physically mixed” is <em>incorrect</em>. The substances in a mixture retain their properties.
“Both will float because they react chemically” is <em>incorrect</em>. Iron and sulfur do not react at room temperature. Even if they did, the iron sulfide would sink.
Copper isn’t an atom if I recalled...
The freezing point is your answer
<span>Real gases deviate from ideal gases when there
are conditions such as low temperature and high pressures. Charles' law holds
the pressure constant with varying temperature. Given that there is constant
pressure, low temperatures cause the deviation from the state of ideality. </span>