ATOMS & BONDING
These negatively charged subatomic particles are found outside the nucleus and are involved in chemical bonding.
What are electrons?
Water is described as this because it has slightly positive and slightly negative ends.
What is polar?
Water molecules sticking to one another is known as this.
What is cohesion?
A solution with a pH below 7 is described as this.
What is acidic?
A reaction that releases energy is described by this term.
What is exergonic (exothermic)?
These electrons are found in an atom's outermost shell and determine how it will react with other atoms.
What are valence electrons?
This type of bond holds the hydrogen and oxygen atoms together within a water molecule.
What is a polar covalent bond?
Water molecules sticking to another surface is known as this.
What is adhesion?
Compared with a basic solution, an acidic solution contains a greater concentration of these ions.
What are hydrogen ions (H⁺)?
A reaction that requires an input of energy is described by this term.
What is endergonic (endothermic)?
In this type of bond, atoms share electrons rather than transferring them.
What is a covalent bond?
This weak attraction forms between the slightly positive hydrogen of one water molecule and the slightly negative oxygen of another.
What is a hydrogen bond?
A water strider can stand on water because hydrogen bonds create this property at the water's surface.
What is surface tension?
A solution changes from pH 6 to pH 4. Its hydrogen-ion concentration has increased by this factor.
What is 100 times?
This is the minimum amount of energy required to get a chemical reaction started.
What is activation energy?
An atom gains an electron from another atom. Name the type of bond that can form between the resulting oppositely charged ions.
What is an ionic bond?
Oxygen pulls the shared electrons in H₂O more strongly than hydrogen does. Explain what happens to the charges on the molecule.
What is oxygen becomes partially negative and the hydrogens become partially positive?
Sweating cools the body because the highest-energy water molecules escape as a gas. This cooling process is called this.
What is evaporation (evaporative cooling)?
These substances help maintain homeostasis by resisting sudden changes in pH.
What are buffers?
When smaller molecules join to form a larger molecule and water is released, this reaction has occurred.
What is dehydration synthesis?
Carbon, hydrogen, oxygen and nitrogen are the four major elements found in living organisms. Give their four chemical symbols.
What are C, H, O and N?
Water can dissolve substances such as NaCl because its partially charged ends surround and separate charged particles. This property gives water this common title.
What is the universal solvent?
Lakes resist rapid temperature changes, helping aquatic organisms maintain a relatively stable environment. Identify the property of water responsible and explain why.
What is high specific heat capacity? Water can absorb or release large amounts of energy with relatively little change in its temperature.
Explain how a buffer responds when excess H⁺ is added to a biological solution.
What is the buffer binds/accepts excess H⁺, reducing the change in pH?
A large molecule is split into smaller molecules by adding water. Name the reaction and explain the role of water.
What is hydrolysis? Water is added/used to break the bond joining the smaller units.