What is true about elements that are in the same column group or family

The given question is incomplete. The complete question is:

Which is true of Elements on a periodic table in the same group (family)?

A; Elements in the same family have similar chemical properties because they have the same number of electron shells.

B; Elements in the same family have similar chemical properties because they have the same number of valence electrons.

C; Elements in the same family have few similar properties as they have different numbers of electron shells.

D; Elements in the same family are always the same type of Elements and have the same number of protons.

B; Elements in the same family have similar chemical properties because they have the same number of valence electrons.

Explanation:

Elements are distributed in groups and periods in a periodic table.

Elements that belong to same groups will show similar chemical properties because they have same number of valence electrons. The chemical reactivity of elements is governed by the valence electrons present in the element.

Example: Flourine, chlorine and bromine are elements which belong to Group 17. They have 9, 17 and 35 electrons respectively and contain 7 valence electrons each and need one electron to complete their octet.

answer : one can design an experiment using a liquid and an additive that can be added to the liquid and observe the chemical changes in the reaction species.

one would need a beaker which is filled with a known amount of the liquid in which thermometer is placed to measure the temperature changes; after addition of the additive to the liquid solution one can note down the temperature change and find whether the reaction is endothermic or exothermic in nature. by subtracting the initial temperature value with the final temperature one can find the temperature changes.

various combinations of liquid and additive can be used. liquid in this case can be a known quantity of water and additives can be epsom salt or without epsom salt the experiment can be conducted to notice the changes. water and ice, hydrogen peroxide and dry yeast, vinegar and baking soda,etc.

the answer is barium and copper bromide