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.
Answer: 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.
I think it's Potassium iodide because it has the highest solubility at 25°C.
Methane.
Water - H2O
Methane - CH4
Methane has 2 more hydrogens than water.
Answer:
B
Explanation:
Cause metamorphic rock is formed by heat pressure overtime
Answer : The products are Silver sulfide,
and Sodium iodide,
.
Explanation :
The given balanced chemical reaction is,

From the given balanced reaction, we conclude that the 2 moles of silver iodide react with the 1 mole of sodium sulfide to give product as 1 mole of silver sulfide and 2 moles of sodium iodide.
In a chemical reaction, reactants are represent on the left side of the right-arrow and products are represent on the right side of the right-arrow.
Therefore, in a chemical reaction the products are Silver sulfide and Sodium iodide.