Recall that a period is horizontal, and a group is vertical.
So if cobalt is moving "down" a period, it would be most logical to say that it would be Ni, or nickel. It could also be Copper, Zinc, Gallium, and so on. Make sense?
No of electrons is equal to no of protons so it will have 10 protons
Two scientists testing different hypotheses about the same question
Answer:
When water is added to a graduated cylinder, having a surface where the sides of the water look higher than the center means that the curved surface is a concave meniscus which has formed because of surface tension (Choice C).
Explanation:
A meniscus is simply the curvature that the surface of a liquid acquires when it is in a container, such as a graduated cylinder. It is concave when there is attraction between molecules -water and glass- or it can be convex when both surfaces are repelled.
<u>Water is a polar molecule</u>, with the capacity to adhere to the surfaces it comes into contact with. This characteristic causes it to form a concave meniscus, as the outermost molecules adhere to the glass surface, while the surface tension of the water attracts the molecules from the centre downwards, causing the concavity.
Learn more:
Measuring with a graduated cylinder brainly.com/question/4070509