B. It's a test given to all geologists.
C. It's named after a scientist who studied tornadoes.
D. It's a numerical rating system that measures the largest seismic waves during an earthquake.
Answer: Directional Selection
Explanation: Directional selection results in a covariance between the trait and fitness and can lead to changes in a trait in a population.
it expands when it freezes
it dissolves solutes
Answer: Option (a) is the correct answer.
Explanation:
A water molecule contains two hydrogen atoms and one oxygen atom. The chemical formula of water is .
Here, hydrogen is electropositive whereas oxygen atom is electronegative in nature. Hence, oxygen atom pulls electrons from hydrogen atom and as a result partial positive charge develops on hydrogen and partial negative charge develops on oxygen atom.
Therefore, molecule of water becomes polar in nature.
Thus, water is considered a polar molecule because it has partial positive and negative charges at each end.
Answer:
The answer is It has partial positive and negative charges at each end.
Explanation:
When a neutral molecule has a positive area at one end and a negative area at the other, it is a polar molecule. Water is a polar molecule, because there is an irregular distribution of electron density in it. This means that water has a negative partial charge near the oxygen atom and a positive partial charge near hydrogen atoms.