Elements in the same group tend to have very similar properties (D). This is due to the number of valence electrons each group has.
Answer:

Explanation:
The formula for molality is:

There are 0.210 moles of KBr and 0.075 kilograms of pure water.

Substitute the values into the formula.

Divide.

The molality is <u>2.8 moles per kilogram</u>
Answer:
1. Rubidium metal reacts very rapidly with water to form a colorless basic solution of rubidium hydroxide (RbOH) and hydrogen gas (H2).
2. Rubidium sinks because it is less dense than water. It reacts violently and immediately, with everything leaving the container. Rubidium hydroxide solution and hydrogen are formed.
Answer:
the input force would be 75 N
Explanation:
if the output force is 150 N you divide that in half which leaves with 75 N !! :)