What substances make up water?

Water is a clear, tasteless, odorless chemical substance that’s essential to all living things on this planet. Water is made up of hydrogen and oxygen pure substances, which can happen in three phases: solid, liquid, or gas. These phases depend on the increase and decrease of temperatures and pressures applied to it. In most cases, water on earth is in its liquid form at an ambient temperature and pressure, but when heat is applied and reaches its boiling point (212°F or100°C) it turns into a gas and evaporates. When it cools down up to its freezing point (32°F or 0°C), the molecules of the water slow down and stick together to form ice crystals.

What is the structure of a water molecule?

Water is a tiny molecule called Dihydrogen Monoxide (H2O). Water molecule forms a 104.45° angle with one negative charge oxygen atom at the vertex and two positive charge hydrogen atoms at the tips. They cling to each other because of the hydrogen binding force. The oxygen atom has a high electronegativity displacing shared electrons towards it greater than the hydrogen. The unequal share of electrons creates a partial negative end on the oxygen and partial positive ends on hydrogen. The lone pairs adapt into a bent structure as the oxygen electrons exert a repulsive effect.

The structure of water is significant in its chemical behavior. This versatile chemical substance is known to be “the universal solvent” with its ability to dissolve almost all other kinds of substances. Water molecules polar combination (2 slightly positive charged hydrogens, and slightly negative charge oxygen) draws other types of polar molecules and ions, called electrostatic attraction (charged-based attraction). Water’s capability to dissolve other substances is significant to human life. It helps transport essential nutrients and oxygen throughout the human body, and it also has a significant role in pharmacokinetics by potentiating drugs (water-soluble drugs) to be absorbed more rapidly.

Although water is regarded to be “the universal solvent” it isn’t entirely true in some cases. Water cannot dissolve non-polar molecules such as oils, fats, some organic solvents, and some compounds like naphthalene. (smilebox.com) Non- polar substances form tight membranes where water cannot pass through, thus making those insoluble to water. 

Is water a compound or an element?

In ancient times, water was considered an element. People believed that nature is made up of five classical elements:  earth, water, fire, air, space. As modern science has risen, elements are re-defined as pure substances that cannot be broken down into simpler forms unless by a nuclear chemical reaction. When two or more elements are held together through chemical bonds (covalent, polar covalent, and ionic bonds), a chemical compound is produced, such as water. Water is composed of one oxygen atom and two hydrogen atoms making its chemical formula H2O. Thus, water is a compound, not an element.

What is the difference between tap water and distilled water?

Potable water or the water that we drink can either come from a tap or distilled water.  What is the difference between the two? Is tap water safe to drink, or is distilled water safer?

Tap water is the most cost-effective and convenient source of drinking water as it comes directly from your home pipes. In some areas, drinking tap water is safe, especially in rural areas where there’s no big threat of water pollution. However, since it comes out directly from valves, cross-contamination may occur. Thus, drinking tap water has a higher risk of acquiring health problems?

Distilled water on the other hand, is believed to be safer to drink. It  has gone through a distillation process where water is boiled into vapor and condensed back to its liquid form. The process will separate solid contaminants and minerals from pure water. 

What substance makes up water when in steam?

When water is heated and reaches its boiling point, water molecules increase its kinetic energy and expand into vapor. Although it changes its physical state, there is no difference between liquid and gaseous water in its chemical composition. The same pure substance of oxygen and hydrogen is present on a water molecule.

What substance makes up water when it’s frozen?

When water temperature decreases to below 0 °C or 32 °F, water reaches its freezing point. Water molecules’ kinetic energy slows down and stabilizes into a hexagonal pattern. Just like water in its gaseous state and liquid states, frozen water contains the same pure substance of oxygen and hydrogen. 

What are the chemical and physical properties of water?

Chemical properties include self-ionization capabilities when it is in liquid form at an ambient temperature. It also has geochemistry properties called weathering (the conversion of solid rock into soil and sediment) and metasomatism (mineral hydration causing the rock to turn into clay).  Water’s pH balance is 6.5 and 8.5, and when it is in its purest form, the pH level is 7.

Water’s physical properties include its appearance depending on its state. It can appear crystalline white when in solid form, transparent in liquid form, and colorless in gaseous form. Pure water is a good insulator, but when ion concentration increases, its electrical conductivity also increases. Water has strong hydrogen bonding properties and polar covalent properties. Water has electromagnetic absorption properties that can absorb most of the wavelengths in the electromagnetic spectrum.