Question

1. in the following chart, fill in the missing property, definition, or example.

property definition example
cohesion attraction between molecules of the same substances water droplets form on a leaf
adhesion water sticks to other substances water climbing up a paper towel or plant stem.
universal solvent dissolving substances in a solution. sugar or salt dissolving in water,
long island stays moderate all year round because it is surrounded by water
heat capacity amount of energy needed to raise a substances temperature by making its molecules move faster icy lakes remain frozen on top but is in liquid form below allowing fish to survive in cold environment.

1. write true or false for each statement. if it is false, correct the incorrect part of the statement to make the statement true.

ex: false, oxygen is negative, hydrogen is positive. in a water molecule oxygen
a) has a positive charge and hydrogen has a negative charge.
b) false, attraction between molecules of the same substances cohesion is the attraction of water molecules to each other.
c) false, its cohesion that allows spiders to walk on water. the property of water called adhesion allows spiders to walk across the surface of water.
d) true water can only dissolve polar substances such as sugar and salt.
e) false, because it is less dense than liquid water the reason why ice floats in liquid water is because it is more dense than liquid water.
f) false, it does take a lot of energy it does not take a lot of energy to heat up or cool down water.

Explanation:

a) In a water - molecule, oxygen is more electronegative and has a partial negative charge, while hydrogen has a partial positive charge.
b) Cohesion is correctly defined as the attraction between molecules of the same substance, so the original statement was wrong in its charge - description.
c) The property that allows spiders to walk on water is surface tension which is a result of cohesion, not adhesion.
d) Water is a polar molecule and can dissolve polar substances like sugar and salt.
e) Ice is less dense than liquid water, which is why it floats.
f) Water has a high heat capacity, meaning it takes a lot of energy to heat up or cool down.

Answer:

a) False, In a water molecule oxygen has a partial negative charge and hydrogen has a partial positive charge.
b) False, Cohesion is the attraction of water molecules to each other.
c) False, Its cohesion that allows spiders to walk on water.
d) True
e) False, because it is less dense than liquid water.
f) False, It does take a lot of energy to heat up or cool down water.