Se - 78
Selenium - 78
or
78/34 Se2-
the unnamed spacecraft which travels to Mars, will have the greatest weight on the Earth.
Answer:
3.1°C
Explanation:
Using freezing point depression expression:
ΔT = Kf×m×i
<em>Where ΔT is change in freezing point, Kf is freezing point depression constant (5.12°c×m⁻¹), m is molality of the solution and i is Van't Hoff factor constant (1 For I₂ because doesn't dissociate in benzene).</em>
Molality of 9.04g I₂ (Molar mass: 253.8g/mol) in 75.5g of benzene (0.0755kg) is:
9.04g ₓ (1mol / 253.8g) = 0.0356mol I₂ / 0.0755kg = 0.472m
Replacing in freezing point depression formula:
ΔT = 5.12°cm⁻¹×0.472m×1
ΔT = 2.4°C
As freezing point of benzene is 5.5°C, the new freezing point of the solution is:
5.5°C - 2.4°C =
<h3>3.1°C</h3>
<em />
Answer:
C. A ball dropped from a height of 10 m will hit the ground at a higher speed than an identical ball dropped from a height of 5 m.
Explanation:
The statement of the hypothesis is that " the greater the height from which you drop a ball, the faster the ball will be traveling when it hits the ground because gravity has more time to speed it up ".
The hypothesis statement is quite explicit. We can deduce that objects at a higher height above the ground will hit the ground much more faster and harder compared to those at a shorter height.
A ball at height of 10m is expected to drop with a higher speed on the ground compared to an identical ball at a height of 5m.
If the balls are at the same height, they are expected to fall with the same speed so far they are identical. Also, a ball at a shorter height will fall at a lower speed.
