Answer:
Element Atomic Number Atomic Mass
Nickel 27 58.6934
Cobalt 28 58.9332
Copper 29 63.546
Zinc 30 65.39
Explanation:
Answer: I think the alcohol molecules slip between the water molecules and take up that space, so you have less that you started with.
Explanation:
<u>Answer: </u>
A sample initially contained 150 mg of radon-222. After 11.4 days only 18.75mg of the radon-222 in the sample remained where 3 half-lives have passed
<u>Explanation:</u>
Given, the initial value of the sample,
= 150mg
Final value of the sample or the quantity left, A = 18.75mg
Time = 11.4 days
The amount left after first half life will be ½.
The number of half-life is calculated by the formula

where N is the no. of half life
Substituting the values,


On equating, we get, N = 3
Therefore, 3 half-lives have passed.
Answer:
Molecules along the surface of a liquid behave differently than those in the bulk liquid.
Cohesive forces attract the molecules of the liquid to one another.
Water forming a droplet as it falls from a faucet is a primary example of surface tension.
Explanation:
Surface tension is the force that stretches the liquid surface. This force acts normal to the surface. It is the downward force that acts on the surface of the liquids which is due to the cohesive forces of the liquids.
The water molecules are bonded by a strong hydrogen bond force which is between hydrogen atom and the electronegative oxygen atom. At the surface the water molecules are attracted strongly by other water molecules which lies below the surface and are stretched at the surface. Thus the water molecules at the surface acts differently than in the bulk liquid.
Mercury have a strong cohesive force than the water and have a higher surface tension force than the water.
Surface water acquires minimum surface area, hence acquiring spherical shape of water.