Answer:
Elements in the same group have the same number of valence electrons.
Explanation: Science.
Answer:
a. The phenolphthalein acts as a color changing indicator to signal the endpoint of the reaction.
Explanation:
Phenolphthalein is an organic substance with chemical formula
.
It is a substance commonly used in acid-base titrations to indicate the end point in the titration because phenolphthalein is colorless in acidic solutions but turns a purplish-pink color in basic solutions.
In this way it helps visually to notice when the final point of the titration has been reached.
I believe dimensional analysis
<span>pb(no3)2 + 2 nacl → pbcl2 + 2nano3</span>
Answer: Rotation cause by the earths orbit and gravity
Explanation: