CHEMISTRY PRELIMS

1. What is matter?

Anything that occupies space and has mass/weight.

2. What is mass?

The amount of matter an object contains.

3. What is weight?

The force exerted on mass by gravity.

4. Do solids have definite shape and volume?

Yes

5. How are particles arranged in solids?

Packed tightly and vibrate in place.

6. Do liquids have definite shape?

No, they take the shape of the container.

7. How are particles arranged in liquids?

Loosely packed and able to flow.

8. Do gases have definite volume?

No, they spread out to fill the container.

9. What is plasma?

An ionized gas with electrically charged particles.

10. What is the 5th state of matter?

Bose–Einstein Condensate (BEC).

11. What happens to atoms at extremely low temperatures?

They clump and act as one super atom.

12. What is a physical property?

A property observed without changing the substance.

13. What is a chemical property?

A property observed when a substance changes into a new one.

14. What is an intensive property?

A property that does NOT depend on the amount of matter.

15. What is an extensive property?

A property that depends on the amount of matter.

16. What is a pure substance?

A substance with uniform composition and fixed properties.

17. Two types of pure substances?

Elements and Compounds.

18. What is a mixture?

A combination of substances with no chemical bonding.

19. What is a homogeneous mixture?

A mixture with uniform appearance throughout.

20. What is a heterogeneous mixture?

A mixture where components are visibly different.

21. What is a suspension?

A mixture where particles settle out over time.

22. What is a colloid?

A mixture with particles that stay suspended.

23. What is a solution?

A homogeneous mixture where solute dissolves in solvent

LESSON 2

LEZGOOO 

1. What is sedimentation?

Settling down of solid particles at the bottom.

2. What is decantation?

Pouring out the clear liquid (supernatant) from settled solids.

3. What is flotation?

Using air bubbles to lift particles to the surface.

4. What is evaporation?

Removing a liquid to leave behind a dissolved solid.

5. What is the solid left after evaporation called?

Residue

6. What is mechanical separation?

Using tools like forceps, magnets, or sieves to separate components.

7. What is filtration?

Separating solid from liquid using a filter.

8. What is the solid left on the filter called?

Precipitate

9. What is centrifugation?

Spinning a mixture to speed up settling of particles.

10. What is distillation?

Separating liquids by different boiling points.

11. What is fractional distillation?

Separating liquids with close boiling points.

12. What is chromatography?

Separating substances based on movement through a medium.

13. What is charcoal filtration?

Using activated charcoal to remove odors and colors.

14. What is sublimation?

A solid changing directly to gas without becoming liquid.

LESSON 3 LEZZGOII

KAYANG KAYA MO YAN

1. What is an atom?

The smallest particle of an element that retains its identity.

2. Who first proposed the idea of “atomos”?

Democritus

3. What did Dalton propose?

Atoms are indivisible and form compounds in fixed ratios.

4. What did Thomson discover?

Electrons

5. What is the Plum Pudding Model?

Atoms are a sphere of positive charge with electrons embedded.

6. What did Rutherford discover?

The nucleus and that atoms are mostly empty space.

7. What did Bohr propose?

Electrons orbit the nucleus in fixed energy levels.

8. What is the modern atomic model called?

Quantum Mechanical or Electron Cloud Model.

9. What is the charge of a proton?

Positive

10. What is the charge of a neutron?

Neutral

11. What is a charge of an electron

Negative

12. Where are protons and neutrons located?

In the nucleus.

13. Where are electrons found?

In energy levels around the nucleus.

14. What is atomic number (Z)?

The number of protons.

15. What is atomic mass (A)?

Number of protons + neutrons.

16. What are isotopes?

Atoms with the same number of protons but different neutrons.

17. What is electron configuration?

Arrangement of electrons in an atom’s orbitals.

18. What is the Aufbau principle?

Electrons fill the lowest energy levels first.

19. What is Hund’s Rule?

Electrons occupy orbitals singly before pairing.

LESSON 4

MALAPIT NA

Johann W. Dobereiner's Contribution

Grouped elements with similar properties into triads, proposing the Law of Triads.

Periods on Periodic Table

The horizontal rows of elements.

Groups (or Family) on Periodic Table

The vertical columns of elements that have similar physical and chemical properties.

What is Electronegativity

The relative ability of a covalently bonded atom to attract shared electrons.

What is Metalloids

Elements adjacent to the zigzag line that exhibit properties of both metals and nonmetals.

What is Ionization Energy

The energy required to remove an electron from a neutral atom in its gaseous phase.

Henry Moseley's Contribution

Discovered the relationship between X-ray frequency and the number of protons (atomic number).

Johann W. Dobereiner's Contribution

Grouped elements with similar properties into triads, proposing the Law of Triads.

Group 1A (or 1) Name

Alkali Metals

Dmitri Mendeleev's Contribution

Arranged elements by increasing atomic weight, observing that similar properties recurred periodically.

What is Electron Affinity

The ability of an atom to accept an electron; the energy change when an electron is added.

What is Valence Electrons

Electrons in the outermost energy level, responsible for the combining capacity of an element.

What is Modern Periodic Law

The properties of the elements are periodic functions of their atomic numbers.

What is Atomic Radius

One-half the distance between the nuclei of two like atoms joined by a single bond.

What is Inner Transition Elements

The Lanthanide and Actinide series, also known as f-block elements.

What is Atomic Radius Trend

Increases from top to bottom within a group; decreases from left to right within a period.

Group 7A (or 17) Name

Halogen Family

What is Law of Triads

The middle element in a triad had an atomic weight that was the average of the other two members.

What is Law of Octaves

Elements exhibit similar behavior to the eighth element following it in the table.

What is Transition Elements

Group B elements (Groups 3-12), also known as d-block elements.

Group 8A (or 18) Name

Noble Gases

What is Representative Elements

Groups 1, 2, and 13 to 17. Their outer energy level is incomplete (s or p orbitals).

Group 2A (or 2) Name

Alkaline Earth Metals

What is Metallic Character Trend

Increases to the left and down the periodic table.

John Newlands' Contribution

Arranged elements by increasing atomic weight and proposed the Law of Octaves.