Water
1. Label the Hydrogens and the Oxygen.
2. Label where you would find a covalent bond.
3. Bond another water molecule to this water molecule pictured by using the draw tool.
4. Label where you would find a hydrogen bond.
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5. How does cohesion of water molecules occur? (Explain cohesion)
Water molecules stay close to each other due to hydrogen bonding. When water is in a
liquid state, hydrogen bonds frequently form, break, and re-form. This causes many
water molecules to be bonded together. Hydrogen bonds collectively hold water
together, and this is called cohesion.
6. What is polarity?
Polarity in chemical bonding, the distribution of electrical charge over the atoms joined
by the bond. The polarity of bonds mainly arises from the act between molecules and
atoms with various electronegativities. + and - attract
7. Is water polar or nonpolar?
Water is a polar molecule. While the overall charge of the molecule is neutral, the
orientation of the two positively charged hydrogens (+1 each) at one end and the
negatively charged oxygen (-2) at the other end give it two poles. This property causes
Water
water molecules to be weakly attracted to other water molecules (positive to negative,
negative to positive) and results in the cohesion of water to itself.
8. How does adhesion of water molecules occur? (Explain adhesion)
Adhesion is the attraction of molecules of one kind for molecules of a different kind,
and it can be quite strong for water, especially with other molecules bearing positive or
negative charges. Chemical adhesion occurs when the surface atoms of two separate
surfaces form ionic, covalent, or hydrogen bonds.
9. What causes water to change phases?
On a molecular level, the intermolecular forces between the water molecules are
decreasing. The heat is providing enough energy for the water molecules to overcome
these attractive forces. All phase changes involve either an increase or decrease of
intermolecular forces.
10. Why is water considered the universal solvent?
Water is capable of dissolving a variety of different substances, which is why it is such a
good solvent. And, water is called the "universal solvent" because it dissolves more
substances than any other liquid. This is important to every living thing on earth.
11. Why can water dissolve most substances?
Primarily, water dissolves many substances because it contains extremely polar
hydrogen bonds. The polarity of the bonds between the two hydrogen atoms and the
oxygen atom means that two sides of the molecule gain different charges – one slightly
positive and one slightly negative. Why do solutes dissolve?
12. What is an ionic compound/bond?
In chemistry, an ionic compound is a chemical compound composed of ions held
together by electrostatic forces termed ionic bonding. The compound is neutral overall,
but consists of positively charged ions called cations and negatively charged ions called
anions.
13. Why does solid ice float on liquid water
Water
Ice is solid so it floats on water because water molecules expand on freezing and form
an open cage-like structure. This means for a given mass ice will have more volume as
compared to liquid water. Thus, being lighter ice floats on water
14. What is capillary action?
Capillary action is defined as the spontaneous flow of a liquid into a narrow tube or
porous material. This movement does not require the force of gravity to occur. In fact, it
often acts in opposition to gravity. Capillary action is sometimes
15. What is surface tension?
the tension of the surface film of a liquid caused by the attraction of the particles in the
surface layer by the bulk of the liquid, which tends to minimize surface area.
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